Dsb's work, what makes them work best?

[barryhc]

Hi folks, let's take a crack at this. We all know that many DSB's work very well. We also know that some have "crashed".

Let's start a discussion about the benefit's of DSB's, along with acknowledging some disadvantages or difficulties that have occured while operating some of them.

No system is a "magic bullet" that negates, or necessarily opposes the functionality of other systems, or support systems, and this certainly includes Deep Sand Beds.

So let's include the use of various "support systems" that are, and can be used in conjunction with a deep sand bed.

Also, all reef systems recieve some kind of maintanence, so let's include what kind of maintanence is performed, and how systems can be operated with less maintnence requirement.

There has been a lot of discussion about Phosphate problems associated with Deep Sand Beds, and that may be true in some instances, and not in others. So this topic is fair game as well.

Let's find out how it occurs, when it does, and why it does, and find out how to reduce it's signifiance, or eliminate it as a problem.

This thread is being started in order to have a discussion on these topics, and how to maintain or improve the functionality of Deep Sand Beds. It is not the place for debate.

This thread is specificly not here to offer a new venue for the BB VS DSB debate, and that type of posting is exceedingly unwelcome.

Let's learn as much as we can about the fuctionality of deep sand beds, and put it to the best use.

Thanks All, and let's enjoy our happy new year!

> barryhc :)

[npaden]

I don't really know that there are that many differences between running a successful tank regardless of what the substrate choice is.

IMO you need to have a handle on nutrient import vs. nutrient export. I choose to handle nutrient export through a large skimmer and a large refugium with macro algae.

I also think good water flow is often overlooked and is possible if planned properly whether you are running a DSB or BB. I have 15,000 gph of flow in my DSB tank.

I'm not sure about your thread title though, if you aren't trying to start a debate your thread title seems to say they are the best and that almost invites a debate.

FWIW, Nathan

[barryhc]

<a href=showthread.php?s=&postid=6451957#post6451957 target=_blank>Originally posted</a> by npaden
I don't really know that there are that many differences between running a successful tank regardless of what the substrate choice is.

IMO you need to have a handle on nutrient import vs. nutrient export. I choose to handle nutrient export through a large skimmer and a large refugium with macro algae.

I also think good water flow is often overlooked and is possible if planned properly whether you are running a DSB or BB. I have 15,000 gph of flow in my DSB tank.

I'm not sure about your thread title though, if you aren't trying to start a debate your thread title seems to say they are the best and that almost invites a debate.

FWIW, Nathan

I have to particularly agree with everything that you say here techincaly.

It wasn't intended that way, and you should know that from reading the initial post, but I will concede that it should have been titled "How do we make them work better than they do currently and the pitfalls that some people have experienced?"

That seems to be a bit too long.

I don't have a side, although I like Sand beds for the look and for the animals that live in them.

The first post remains as self-explanatory.

Thanks Nathan, I hope it isn't taken that way. > barryhc :)

[npaden]

How about, "DSB tips and tricks from the experienced"

I agree whole heartedly about sandbeds for the looks and the animals that live in them. I have several wrasses that sleep by burying themselves in the sand. Also I have a M. Dorensis (Long Tentacled Anemone) that has it's foot firmly attached to the bottom of the glass in my tank in an area where the sand is 8" deep.

FWIW, Nathan

[Doug]

One of the issues that I had when I tried to use a DSB was the lack of life in the sandbed. Even after 6 months, there was very little critter life.

I think my problem came from using already cured live rock that had been in that same tank for a long time. I would guess that if I had used uncured rock or maybe seeded the sandbed with a "critter kit", it might have been successful. I ended up with what looked like six inches of dead sand and a very serious cyano bloom.

[barryhc]

<a href=showthread.php?s=&postid=6452122#post6452122 target=_blank>Originally posted</a> by npaden
How about, "DSB tips and tricks from the experienced"

I agree whole heartedly about sandbeds for the looks and the animals that live in them. I have several wrasses that sleep by burying themselves in the sand. Also I have a M. Dorensis (Long Tentacled Anemone) that has it's foot firmly attached to the bottom of the glass in my tank in an area where the sand is 8" deep.

FWIW, Nathan

Not bad Nathan. Ck. your PM.

> barryhc :)

[barryhc]

I have run into a partially similar situation Doug. I basicly cured the 2nd and larger batch of live rock right in the display tank, and I had no problems at all with algae, or with cyano, but that was because of an abundance of crabs and snails before the live rock was put in.

I'm at 11 mos. and have never had any problem with cyano, or algae, and I don't stir, or vacuum, or siphon, because I have critters that take care of that. I also don't have much of that wanted "fauna" in the sand bed for the same reason.

I have been told that the hermit crabs are really "tough" on the sand bed "fauna", but I have brittle stars, peppermint shrimp, and cucumber as well, and I really don't know enough about "fauna-predation" to correct this yet.

> barryhc :)

[joefish]

I want to aproach this as a learning experience not a confrontation , I hope it works out that way .


I'll be a guinie pig here .My DSB failed not crashed just failed . I want to know why ?

The tank is a 120 , mak4 return with 6 - 1200 maxi jets on a wave maker . The skimmer was a Euro-reef CS 8-2 . I ran carbon and phosban ,that I changed out once a month . Weelky 10% water changes .I had a refugium with assorted maco algaes and a 7"DSB and live rock .

The sand used was southdown the tank had 5" and the refugium had 7".

The total water was 205 gallons minus the area sand and rock took up .

The sand was white and healthy looking while the rocks were covered in a brown turf algae .

I blew the rocks clean three a times a week .

Here's a picture to help with refernces
http://reefcentral.com/gallery/data/500/8920sand.JPG

I am not trying to prove a point . I will answer all questions honostly no matter how bad I look .

I want to know how come some DSB tanks fail and others flourish.

[SDguy]

Hey Barry,

I think you also may have to define what one considers a disfunctional, or not optimal, DSB. What is a crash? Is cyano the defining organism? Algae in general? Coral death? Which kinds...acros, LPS, all?

I have a 3+ year DSB. Only maintenance is by my pistol shrimp, who probably makes it a marginal DSB at best, with such massive excavations:rolleyes: I have algae (halimeda, coralline) and 3 of 4 acros have died. Is this a crash? Everything else is absolutely flourishing. I blame allelopathy and heavy anthia feedings more than my DSB. So I think my DSB is working fine. An SPS keeper would probably dissagree.

Your thought?

[barryhc]

<a href=showthread.php?s=&postid=6452372#post6452372 target=_blank>Originally posted</a> by SDguy
Hey Barry,

I think you also may have to define what one considers a disfunctional, or not optimal, DSB. What is a crash? Is cyano the defining organism? Algae in general? Coral death? Which kinds...acros, LPS, all?

I have a 3+ year DSB. Only maintenance is by my pistol shrimp, who probably makes it a marginal DSB at best, with such massive excavations:rolleyes: I have algae (halimeda, coralline) and 3 of 4 acros have died. Is this a crash? Everything else is absolutely flourishing. I blame allelopathy and heavy anthia feedings more than my DSB. So I think my DSB is working fine. An SPS keeper would probably dissagree.

Your thought?

Well, that is an exceedingly good point, and I meant to offer up in the original post, that such definition should be brought up, and then bantied about until we had something to refer to, but I just forgot, and thanks for bringing it up.

Well we know that some SPS will not tolerate even "fairly low" concentrations of nutrients, and so I would call this an inappropriate matching of system and animal. It would help to know which species have more difficulty, and those that are more tolerant.

So there is one, "Inappropriate". As far as I know, this is primarily relative to some SPS, and also to some Dendros, there may be other instances. This would include "Not Optimal".

Then there would be "Dysfunctional", This might apply to JoeFish's tank, I'm not sure. We might also call this "Failed". It certainly needs some type of description. It sounds like everything is dying or in "decline".

Then there is the "crash". I think that this applies to "Uncontrollable Algae".

Let's have people chime in here, ans we will try to put together good definitions.

Joe, please tell us more about the failure. The picture sure looks nice.

Thanks > barryhc :)

[SDguy]

And with Joe's tank, which is mostly SPS from what I can see, why was the algae bad? Keeping the corals from growing? From spreading on the rocks? Actually invading the skeletal structure of the coral? I'm anxious to hear more Joe :)

[barryhc]

<a href=showthread.php?s=&postid=6452311#post6452311 target=_blank>Originally posted</a> by joefish

I want to know how come some DSB tanks fail and others flourish.

ME TOO!!!

Tell us a little more about the failure, and how we might deal with these definitions.

I have not had a failure, but some people have, and it can't be dealt with unless the bad experiences are considered as well.

Thanks JoeFish! > barryhc :)

[npaden]

I guess my 4 1/2 year old high flow SPS dominated DSB tank is inappropriate then?

http://padens.com//tank_pics_10-2-05/images/fulltank_10-2-05_700.jpg

[J_Geisinger000]

hey npade!!!

how are you getting that much flow without creating a sand storm?

Im getting ready to start an sps only tank and I want a sandbed but was thinking of going bb because of the amount of flow I will have

[Frisco]

The pump tipped the balance!!! :D

[PUGroyale]

<a href=showthread.php?s=&postid=6452701#post6452701 target=_blank>Originally posted</a> by npaden
I guess my 4 1/2 year old high flow SPS dominated DSB tank is inappropriate then?

http://padens.com//tank_pics_10-2-05/images/fulltank_10-2-05_700.jpg

Appropriate??? Who cares :lol: It's stunning :thumbsup: Love to see some closer pics.

I wasn't going to "post" in this thread because "it seems" some of "these" are just "started" to "stir" things up :rolleyes: ...But that's a great looking tank.

[SDguy]

<a href=showthread.php?s=&postid=6452701#post6452701 target=_blank>Originally posted</a> by npaden
I guess my 4 1/2 year old high flow SPS dominated DSB tank is inappropriate then?

http://padens.com//tank_pics_10-2-05/images/fulltank_10-2-05_700.jpg

Excellent point. I don't think we should use the term inappropriate. It suggests an opinion, no actual happening or event (ie crash, algal bloom, STN, etc.)

[barryhc]

<a href=showthread.php?s=&postid=6452701#post6452701 target=_blank>Originally posted</a> by npaden
I guess my 4 1/2 year old high flow SPS dominated DSB tank is inappropriate then?

http://padens.com//tank_pics_10-2-05/images/fulltank_10-2-05_700.jpg

Only if it is having a problem, and it certainly does not seem to be having a problem. Beautiful tank!!

I really like the deeper "ends". Can you tell us about your substrate?

> barryhc :)

[Airman]

Joe,
How did your tank fail? Algae growing on rock is natural.

Npaden,

How big is that clam in the middle?

[kbmdale]

<a href=showthread.php?s=&postid=6452621#post6452621 target=_blank>Originally posted</a> by barryhc


Then there is the "crash". I think that this applies to "Uncontrollable Algae".


Thanks > barryhc :)


but that may or may not have anything to do with the dsb...there is no way to know, and the sand seems to be the easiest thing to blame...

[npaden]

Thanks for the kind words on the tank. It has been through some tough times but I'm happy with it.

<a href=showthread.php?s=&postid=6452712#post6452712 target=_blank>Originally posted</a> by J_Geisinger000
how are you getting that much flow without creating a sand storm?

Im getting ready to start an sps only tank and I want a sandbed but was thinking of going bb because of the amount of flow I will have

Having a 10 foot long tank helps some on keeping the flow from hitting the opposite wall and slamming back down to the sand.

I use tunze streams and try to limit the output of my closed loop and return pump to under 5 feet per second.

At one point the sand in my tank was pretty much evenly across the tank. The flow in the tank over the years has distributed the sand out of the more high flow center of the tank and piled it up on the ends of the tank. The sand on the ends of the tank is about 8" deep now and the sand in the middle is only around 2" deep.

Again, I think high flow is a key to a successful tank, regardless of the sediment.

FWIW, Nathan

[sradmin]

Wow, so many variables to quantify- Why some dsb tanks "fail" and why others thrive. It's just so difficult to know exactly what's happening within any given area of a sand bed. A search of RC will yield many DSB crash stories that don't appear to be caused by improper husbandry and/or improper set-up. Maybe it would help to identify possible variables between long-term successful dsb tanks and ones that have had problems?

[kbmdale]

nathan your tank looks great, what kinda light are you running it looks a little more yellow than ussual.

[joefish]

<a href=showthread.php?s=&postid=6452621#post6452621 target=_blank>Originally posted</a> by barryhc


Then there would be "Dysfunctional", This might apply to JoeFish's tank, I'm not sure. We might also call this "Failed". It certainly needs some type of description. It sounds like everything is dying or in "decline".

Then there is the "crash". I think that this applies to "Uncontrollable Algae".

Let's have people chime in here, ans we will try to put together good definitions.

Joe, please tell us more about the failure. The picture sure looks nice.

Thanks > barryhc :)

http://reefcentral.com/gallery/data/554/8920red_mil.JPG

http://reefcentral.com/gallery/data/555/8920PRMC.JPG

Don't look at the coral , look at the algae behind it .:p
The problem is that brown hair/turf algae.

No losses , colors was alright .

I could not get that algae to receed at all . I would have to scrape it out of the way to glue on a frag .

[joefish]

<a href=showthread.php?s=&postid=6452641#post6452641 target=_blank>Originally posted</a> by SDguy
And with Joe's tank, which is mostly SPS from what I can see, why was the algae bad? Keeping the corals from growing? From spreading on the rocks? Actually invading the skeletal structure of the coral? I'm anxious to hear more Joe :)

It would keep Frags from gatting a good hold on the rock , other then that nothing ..


A ps to all of this is everything seemed to grow very slow .

[joefish]

<a href=showthread.php?s=&postid=6452864#post6452864 target=_blank>Originally posted</a> by Airman
Joe,
How did your tank fail? Algae growing on rock is natural.



Coralin or film yes , not this kind .

[joefish]

<a href=showthread.php?s=&postid=6452654#post6452654 target=_blank>Originally posted</a> by barryhc
ME TOO!!!

Tell us a little more about the failure, and how we might deal with these definitions.

I have not had a failure, but some people have, and it can't be dealt with unless the bad experiences are considered as well.

Thanks JoeFish! > barryhc :)

My definition of:

Crash = sudden deaths that occure fast .

Failed= not working right.

[bertoni]

I've seen a tank that had a similar turf algae problem, and I don't recall it being a DSB tank. I'm not sure that this problem is a DSB problem per se, but it could be more like an Aiptasa problem: an invasive species that happens to do well in our ecosystems. A natural predator of the various turf algae might help. I'm not convinced a DSB would necessarily help or hurt in this type of situation. Hard to say.

[joefish]

<a href=showthread.php?s=&postid=6452701#post6452701 target=_blank>Originally posted</a> by npaden
I guess my 4 1/2 year old high flow SPS dominated DSB tank is inappropriate then?



No not inappropriate , but set up correctly .


Very nice by the way .:p

[kbmdale]

lighting has alot to do with growth as well...WHat kinda lighting are you running JOE. I have learned on my own and from paulb's tank threads that it seems that letting some algae grow actually helps the tank more than it hurts. Are you running a fuge?

[joefish]

<a href=showthread.php?s=&postid=6452886#post6452886 target=_blank>Originally posted</a> by kbmdale
but that may or may not have anything to do with the dsb...there is no way to know, and the sand seems to be the easiest thing to blame...

<a href=showthread.php?s=&postid=6453218#post6453218 target=_blank>Originally posted</a> by bertoni
I've seen a tank that had a similar turf algae problem, and I don't recall it being a DSB tank. I'm not sure that this problem is a DSB problem per se, but it could be more like an Aiptasa problem: an invasive species that happens to do well in our ecosystems. A natural predator of the various turf algae might help. I'm not convinced a DSB would necessarily help or hurt in this type of situation. Hard to say.

I must put in my discaimer now

( I believe DSB can work , I am not advocating anyone to follow in my foot steps )

The reason I know it was the DSB is simple .

First I removed the DSB in the refugium , I noticed a slow down in the alage growth .

Then I removed the refugium all together and it slowed down a lot more , but still not receeding

Then I removed the DSB in the tank .

And finaly I had it receeding .

Through this I believe my DSB failed .

Through the time of the DSB I had 0 NO3 , after I had a trace but the algae was leaving .

This is my DSB failure story and not ment to have anyone go BB . DSB can work mine just failed and I don't know why .

this was a few days after the change over .
http://reefcentral.com/gallery/data/500/8920FT.JPG

and a month later
http://reefcentral.com/gallery/data/586/8920CL_tank.JPG

4 months later
http://reefcentral.com/gallery/data/500/89209-11-04.JPG

[kbmdale]

Well that would lead me to the same conclusion...Good proof of the failure. Now what could you have done differently that might have kept it from happening or proloned the issue. Any ideas?

[joefish]

<a href=showthread.php?s=&postid=6453239#post6453239 target=_blank>Originally posted</a> by kbmdale
lighting has alot to do with growth as well...WHat kinda lighting are you running JOE. I have learned on my own and from paulb's tank threads that it seems that letting some algae grow actually helps the tank more than it hurts. Are you running a fuge?

The lighting was always 250w MH's .

I was .

[joefish]

<a href=showthread.php?s=&postid=6453339#post6453339 target=_blank>Originally posted</a> by kbmdale
Well that would lead me to the same conclusion...Good proof of the failure. Now what could you have done differently that might have kept it from happening or proloned the issue. Any ideas?


That's why I'm here .:lol:

[J_Geisinger000]

wow joe those corals look like they grew from the one month pic to the 4 month pic

[kbmdale]

Joe how deep was the sandbed, how old was the sandbed, and what kinda of sand? Might help with the resolution.

[joefish]

<a href=showthread.php?s=&postid=6453398#post6453398 target=_blank>Originally posted</a> by J_Geisinger000
wow joe those corals look like they grew from the one month pic to the 4 month pic

Thanks ,and yes they did . That is another reason I feel my DSB failed . I also think the increase of flow helped the growth . With a 4' tank , too much flow and sand don't mix well .

I want to know what I was doing wrong with DSB . It's frustrating to see others do it right and I couldn't . Plus Id rather look at sand then SB .;)

[joefish]

<a href=showthread.php?s=&postid=6453420#post6453420 target=_blank>Originally posted</a> by kbmdale
Joe how deep was the sandbed, how old was the sandbed, and what kinda of sand? Might help with the resolution.

South down , between 4-5" .

It was close to 2 yrs when I changed it out .

[kbmdale]

That sounds about right, maybe it ran its course. I winder if you had replaced it with another dsb if the problem would have been solved like it was by removing it. 2 years is actually pretty good on a dsb from alot you read on this site. Did you ever syphon or stir it?

[joefish]

<a href=showthread.php?s=&postid=6453532#post6453532 target=_blank>Originally posted</a> by kbmdale
That sounds about right, maybe it ran its course. I winder if you had replaced it with another dsb if the problem would have been solved like it was by removing it. 2 years is actually pretty good on a dsb from alot you read on this site. Did you ever syphon or stir it?

Well I was battling the algae for close to a year so I got one good year out of it .

I still went wrong somewhere .

I would siphon anything that didn't look pure white and I stired the rest .

[capncapo]

I would hardly consider two years to be the norm or even acceptable as the lifespan of a properly set up and maintained DSB.

[rulesmith]

I would like to know the definition of a deep sand bed. How many inches are we talking here? I currently have a 55 gal. reef that has an average of 4 inches of sand. I am in the middle of building a 500 gal total water system. The display is 360 and I know I am going to have sand, but I do not know how much. From fear of "crashes" whatever the definition of those are, I have been leaning towards just having about 2 inches of sand in the new tank.

[kbmdale]

<a href=showthread.php?s=&postid=6453750#post6453750 target=_blank>Originally posted</a> by capncapo
I would hardly consider two years to be the norm or even acceptable as the lifespan of a properly set up and maintained DSB.

You would hope to get more life but I stated that from what you read here on this site.

but thats the question, what is a properly set-up and maintained dsb.

[joefish]

<a href=showthread.php?s=&postid=6453769#post6453769 target=_blank>Originally posted</a> by rulesmith
I would like to know the definition of a deep sand bed. How many inches are we talking here? I currently have a 55 gal. reef that has an average of 4 inches of sand. I am in the middle of building a 500 gal total water system. The display is 360 and I know I am going to have sand, but I do not know how much. From fear of "crashes" whatever the definition of those are, I have been leaning towards just having about 2 inches of sand in the new tank.

I've read Dr Ron say that at least 4' is required . Then I heard durring a presentation Anthony Calfo say that 7" is needed to work for a True DSB .

I would go for 1" or go to 4" not inbetween .

[kbmdale]

I agree with joe everything I have ever read has stated under 1" for SSB, over 4" for dsb. anything in between is a no no..Now with that said wonder why and how they now that.

[boxfishpooalot]

I think if you use a gravel vacume on one side of the dsb, then do the other side 2 months later you could extend the life of a dsb.

Nature uses this meathod too, it called a hurricane.

[kbmdale]

might be a valid point BOX...Has anyone been doing this

[Airman]

Joe how big was your bio load before and after your algae problem. Was your macro algae growing at a good rate?

[joefish]

<a href=showthread.php?s=&postid=6454039#post6454039 target=_blank>Originally posted</a> by Airman
Joe how big was your bio load before and after your algae problem. Was your macro algae growing at a good rate?

6 fish before and after .

Macro was growing like mad , then slowed down after the DSB was removed from the refugium .

[capncapo]

From what Dr. Ron said:

Rule #1. You don't vacuum a DSB
Rule #2. You don't stir a DSB

His recommended depths wer 4" min. - 8" max.

[boxfishpooalot]

<a href=showthread.php?s=&postid=6454070#post6454070 target=_blank>Originally posted</a> by joefish
6 fish before and after .

Macro was growing like mad , then slowed down after the DSB was removed from the refugium .

I noticed this also. My macro is not growing anymore. At least its very slow anyway under the 400watt halide.

[kbmdale]

i don't think macro would respond to well to 400w of light..lol... i grow mine under 20w

[npaden]

One thing that has always confused me over DSB "failures" is that many of the tanks are relatively young. If the DSB is actually a phosphate sink then for the first couple years there shouldn't be any algae problems, but many people have issues within 1 year or even less.

Joe, beautiful tank. My tank went through some similar issues around the 2 year mark and like yours mine turned the corner and the algae went away and coral growth took off. The difference was that I didn't remove any sand.

I have a hard time figuring out why one tank works and another doesn't. One thing I noticed in the pics is that you went from a bunch of maxijets to tunze streams. Probably triple the water flow. Not sure if that has anything to do with it or not.

When my tank cleared up I added a tunze stream and switched from iwasaki bulbs to xm 10k bulbs. No idea if that had anything to do with anything or not.

Just some more food for thought.

[romanr]

One thing about keeping a specific depth is that your tank inhabitants might make this impossible. My sand bed is about 5 in deep in 50% of the tank, 3 in deep in 25% of the tank and 2 in deep in the other 25%.

I think the key to a successful DSB is your infauna population and diversity as well as your clean-up crew for the top 1/2 inch layer of your sand bed.

In my tank I have various worms (spaghetti, bristle, several other yet unidentified species), amphipods, copepods, micro-stars. The population of these change with one blooming to high numbers, only to decline and being superceded by another.

My clean-up crew is composed of 6 or so sea cucumbers of two varieties.

No, my DSB is not without problems. I need to recruit some other creature to my clean-up crew to take care of some diatoms and algae found on some spots in the sand bed. I need to make it a point to replenish my infauna with more critters on a yearly basis to keep the needed diversity in my tank. But overall I am please with the results and made my decision to go with a DSB for the following 2 reasons.
1) I'm lazy and don't want to be cleaning detritus all the time. The sand bed does turn into a magical sink where all the bad stuff goes in and disappears. Yes I'm not stupid and know that it doesn't really disappear but it does get consumed/broken down to acceptable levels and makes maintenance a breeze. If in a few years my DSB goes to hell then I will slowly replace it and get a few more years out of it.
2) The look of a sandy substrate is not something I am willing to do without. It is simply aesthetically more pleasing in my opinion.

[joefish]

<a href=showthread.php?s=&postid=6454248#post6454248 target=_blank>Originally posted</a> by npaden
One thing that has always confused me over DSB "failures" is that many of the tanks are relatively young. If the DSB is actually a phosphate sink then for the first couple years there shouldn't be any algae problems, but many people have issues within 1 year or even less.

Joe, beautiful tank. My tank went through some similar issues around the 2 year mark and like yours mine turned the corner and the algae went away and coral growth took off. The difference was that I didn't remove any sand.

I have a hard time figuring out why one tank works and another doesn't. One thing I noticed in the pics is that you went from a bunch of maxijets to tunze streams. Probably triple the water flow. Not sure if that has anything to do with it or not.

When my tank cleared up I added a tunze stream and switched from iwasaki bulbs to xm 10k bulbs. No idea if that had anything to do with anything or not.

Just some more food for thought.

Thanks ,

I couldn't put the tunze in there with the sand . It would hit the other end and just stir sand .

Do you have a refugium ?

[kbmdale]

There is a part of this discussion being overlooked that Romanr just touched on..To have a successful DSB you will have to have an areobic area and an anarobic area within the sandbed.

I get what your saying Romanr, and maybe thats why the tank on the first page has worked so well... He has 8" deep zones at the end and 2" in the middle, maybe you need more areobic than anareobic. Of course I have no proof of this...;) but I have a hunch that this could ne the case, I have seen other successful DSB tanks and they all seem to have varieing depths of sand throughout the tank.

[npaden]

I did not have a refugium when I was having algae problems. I got everything ready for my new refugium and was about to get it setup and the nusiance algae disappeared almost overnight.

I went ahead and setup the refugium anyway and now am growing a lot of cheato in there. It is in a greenhouse in full sun. I also setup a larger skimmer.

One other thing that happened to my tank that I attribute some of the problems with was a big drop in salinity while I was on vacation to Fiji one summer. My big Fiji yellow leather died (like 18") and that caused a lot of the problems I think.

That's the issue with a reef tank, there are so many variables it is hard to tie it down to one thing.

FWIW, Nathan

[romanr]

My various depths were not by design but the creation of a clown that loves to stir things up. I was at first concerned that I wasn't realizing the ideal, even sand bed but after unsuccessful attempts at undoing my clown's design and further education on the various substrate theories I decided that it wasn't an all together bad thing to have a DSB with varying depths.

[kbmdale]

Like wise romanr, npaden said his happened because of flow over the years...Just something to think about. I kinda like the look of the varied depths, looks more natural, but very hard to dulicate without a critters help or flow help.

[J_Geisinger000]

Im thinking of going bb for my new 90 gallon sps tank
so that I can get the amount of flow that I want with out having to worry about blowing sand everywhere

[joefish]

<a href=showthread.php?s=&postid=6454531#post6454531 target=_blank>Originally posted</a> by npaden


That's the issue with a reef tank, there are so many variables it is hard to tie it down to one thing.

FWIW, Nathan


Tell me about it . It can also be so frustrating trying to figure the one issue out .:lol:

For a while I went beating my chest like a gorila when My new BB beat my problem for me . After I had time to boast and get it out of my system , I realized I wasn't smart enough to make a DSB work .:(

Now I check threads like this trying to learn what I did wrong so I can beat the DSB monster I built .The other time is spent defending BB which I'm tired of doing . It's just I know how to make them work so I'm stuck in the middle .

So how's that rambling for a stressed out dude trying to be a reefer .http://www.smilieshq.com/smilies/sick0012.gif (http://www.smilieshq.com)

[kbmdale]

<a href=showthread.php?s=&postid=6454585#post6454585 target=_blank>Originally posted</a> by J_Geisinger000
Im thinking of going bb for my new 90 gallon sps tank
so that I can get the amount of flow that I want with out having to worry about blowing sand everywhere

Not being mean, but what does tha have to do with this thread. Clearly npaden isn't having sand storms with his high flow tank.

[romanr]

joefish,
If BB works for you then why change things? Unless there is something your BB is not accomplishing for you (aesthetics, perhaps?)

[npaden]

Yeah, I think Joe's tank looks great.

I think I can get away with the flow in the longer tank. I think to run streams in a tank with fine sand it probably needs to be 6' long or they can't be run full out.

[romanr]

I think that J_Geisinger000 does have a legitimate concern but it is something that many reefers have found a work-around for so it shouldn't be a show stopper unless you don't want to go through the trouble of figuring out how to make the two work together (high flow and DSB).

[kbmdale]

Sorry J_G, Flu talking. What type sand are you using Npaden. I have read more recent stuff on this site that seems to point to aragonite sand not having much advantage, as calcium carbinate tends to bind po4.

[joefish]

<a href=showthread.php?s=&postid=6454660#post6454660 target=_blank>Originally posted</a> by romanr
joefish,
If BB works for you then why change things? Unless there is something your BB is not accomplishing for you (aesthetics, perhaps?)

well do to leaks I'm actualy taking a break for now . I am planning a new setup though .

That was a FYI so you don't think I'm up to something .


Now a new tank would mean options again . I like the look of sand better , of course . So yes to a point aesthetics.:D

I know what I can do with BB , now I want to learn DSB's . There are more critter options with DSB's .

There's other reasons but why get overly boreing .:cool:

[chrismunn]

i have some questions about the DSB.....

am i to understand that a DSB acts as a de-nitifier because of anaerobic processes that happen deep within the sand bed?

if this is so, it leads me to ask the question;

lets say i have a 2+ year old DSB, and everything is well, but then one day while doing routine maintanence, i accidentally dig into the sand bed shifting a large portion of the sand, not only on top, but deep within the sand bed. have i then just ruined my DSB for any lenght of time (short , or long)?

if i HAVE disabled the sand bed from de-nitrifying, what then are the consequeces? will i have numerouse and large, nuisance algae outbreaks? or will the system be able to re-stabilize in time that there would be no effect?

and if this isnt the case, maybe someone should dirct me to a link where i can read more info on the DSB.

the whole idea of a DSB to me is very unclear, but i am a big fan of sand, from an asthetic point of view. although if i felt that a sand bed would ruin my reef, i would definatly go BB, which i am considering for my new 75g.

so, the stated question is my biggest concern regarding a DSB.

if anything i wrote was debate causing, please ignore it!

[joefish]

<a href=showthread.php?s=&postid=6454675#post6454675 target=_blank>Originally posted</a> by npaden
Yeah, I think Joe's tank looks great.

I think I can get away with the flow in the longer tank. I think to run streams in a tank with fine sand it probably needs to be 6' long or they can't be run full out.

Thanks .:D

heres a link to the last picture before dismantleing it .

120g (http://img.photobucket.com/albums/v721/Joefish1/March2605.jpg)


Sorry , that was my baby so I love to show her off . It also goes to show that there are more then one way to keep a reef tank .:p

[npaden]

I have 750lbs of southdown tropical play sand in my tank.

I personally don't worry about disturbing my sand. I don't really intentionally stir it up, but when I move something around (clams mostly) I'll dig around a spot to place them. I've never noticed any issues because of this. I also redid some plumbing a while back and ended up moving a TON of sand. The only issue that I had as a result was a small diatom bloom and some of my sps corals got a little covered in sand for a while and I had to be careful to keep the sand from covering them up and suffocating an area.

FWIW, Nathan

[J_Geisinger000]

hey joe whats on the bottom of your tank
?
I know its a bare bottom but it looks like you have something there or did you paint it?

[joefish]

<a href=showthread.php?s=&postid=6454916#post6454916 target=_blank>Originally posted</a> by J_Geisinger000
hey joe whats on the bottom of your tank
?
I know its a bare bottom but it looks like you have something there or did you paint it?

I'll whisper it , if trolls hear me they will come running .....


Star Board , it's a marine board that is UV resistint .


http://www.smilieshq.com/smilies/scared0012.gif (http://www.smilieshq.com)


:lol:

[romanr]

I learned from experience that a disturbance of a portion of the sand bed will not necessarily spell disaster. I had a powerhead that accidentally got pointed towards the substrate and dug down to the glass in a section that was about 4 in deep. I would say that less than 10% of the sand was impacted and there were no perceived ill-effects from this accident.

[my2girls]

Joe- I don't think you really have a choice. You obviously know how to go BB, that 120 is incredible. Why mess with sand?

Not trying to be controversial, for the record I think the 10 foot tank with DSB is incredible too.

[sherm71tank]

Here 's a link with some decent info. It started out kinda rocky but smoothed out.
http://reefcentral.com/forums/showthread.php?s=&threadid=739856

[J_Geisinger000]

where did you buy that board at?

[joefish]

West Marine .

Not being rude but if you have any other BB questions please PM me . I'd like this thread to stay on track .:)

[kbmdale]

interesting reading on this site

http://www.wetwebmedia.com/deepsandbeds.htm

here is an part of an article that ANTHONY CALFO wrote

"One last mention of the improper implementation of plenum and deep sand bed strategies collectively. We should like to dispel the most common corruption of the application for those interested to know or try it. Severe criticism of their use has faulted them for becoming "nutrient sinks": trapping and accumulating detritus to levels that cripple water quality and fuel nuisance algae growths. The reality of the matter may likely be that an incorrect application of the technology caused the rift. As aquarists, we too often have inadequate water flow, which prevents detritus and organic particulates from being properly exported by protein skimming and other filtration dynamics. In turn, excess detritus settles in pockets and migrates deep into the substrate. Furthermore, course sand and gravel is still quite popular and allows particulates to settle and accumulate rather easily. The killing blow to a flawed application with course substrates in weakly circulated aquarium is the unfortunately popular employment of intermediate depths of sand at 1"-3" (25-75mm). In this mid range, the sand is often too deep to be wholly aerobic and yet not deep enough for efficient denitrifying faculties. As such, the two dominant (and desired!) biological populations are restricted if not excluded at large and the sand bed may become a dead zone... a nutrient sink. However, intermediate sand depths can be maintained successfully (often, in fact!), but require due diligence with regular sifting naturally or mechanically (by the aquarist or by creatures in the aquarium), strong water flow in the tank, realistic bio-loads, etc."

[beachroadbum]

Hey Now all,

I figure my question would do well for this thread as I hope I haven't just done something to prevent my two month old DSB from working properly.
Some facts are that its a 40breeder tank with 5-6 inches of aragamax .1-1.0 sand. I have had it up and running for two months. I added tons of critters and miracle mud etc...from ipsf.com about a week into it...40 pounds of cured live rock also in there.
Yesterday I added my corals which were being housed in another tank. Dr. Ron said to go slow on the addition of adding corals and fish. I have just read where Eric Borneman stated that corals are efficient killing machines.
I am a bit worried that my two months of patience has now ben blown since I added about 10-15 lps and softies in the tank yesterday.
Will corals alone if added too early really decimate infauna populations and prevent a DSB from working properly?

Thanks!

take care,
Jared

[kbmdale]

Nah I don't think adding corals will deplete your infauna, but your dsb is probably not fuly functional yet I have heard that it takes 3-6 months before it actually if fully operational. If I am wrong someone will correst me, so stay tunned for a better answer.

[corals b 4 bills]

When theres a question of algae I start at the beginning. Could there be somthing in the sand you bought? or I've heard of things like concrete inside of the live rock. look into this.

[Thales]

<a href=showthread.php?s=&postid=6454948#post6454948 target=_blank>Originally posted</a> by romanr
I learned from experience that a disturbance of a portion of the sand bed will not necessarily spell disaster. I had a powerhead that accidentally got pointed towards the substrate and dug down to the glass in a section that was about 4 in deep. I would say that less than 10% of the sand was impacted and there were no perceived ill-effects from this accident.

When that happened to me I my tank crashed - lots of bleaching and loss.

[beachroadbum]

Hey Now,

Thanks for the reply kbmdale. Yeah I won;t be adding a fish for a long while yet. I just had to get some corals in there. Water paramaters are great and there are a ton of worm tracks which is a good sign. I just love the life you get with a DSB. It's so natural.

take care,
jared

[kbmdale]

BUMP...

[barryhc]

<a href=showthread.php?s=&postid=6453208#post6453208 target=_blank>Originally posted</a> by joefish
My definition of:

Crash = sudden deaths that occure fast .

Failed= not working right.

I like your definitions here joefish. Boy have you people been busy here!!

It seems that the definition of a sand bed is still highly variable, and will likely stay that way. My point here is that, that variability may very well have contributed to some of the difficulties that people have had.

4" to 6" seems to be the common "minimum" depth. I guess I'd call it 5".

The particular substrate grain sizes and composition are very likely to have a significant effect as well.

Most sand beds are using rather fine sand as has been "reccomended", and this is usually "southdown", which is generally considered to be a mix of "mud" ( .05 to .125mm ) up to 4mm "gravel", or a straight grade of "oolitic" sand ( usually .1 to 1.2mm ). There are of course other variations.

I think the "exclusive use" of these finer muds and sands, has likely contributed considerably to the "sand-storm-problem", and other problems, and it needn't be the case.

Surely, these finer grains contribute to a very large surface area which is beneficial to large bacterial populations, and they are also touted as improving the buffering capacity of the substrate, which is probably true as well, but may not be as significant or beneficial as we have been lead to believe.

The fine grains are also claimed to "reject" detritus better than larger grains, and "on the surface" this would appear to be true, but in the larger picture of our complete reef system, I'm not so sure of this.

Here is my take on the fine grains. Yes, they definitely increase the surface "area", but is this really the "AVAILABLE" surface area? Most if not all of the experts have stated that the aerobic activity is limited to a very shallow depth in these fine grains.

This is because "advection" flow is extremely low in fine grains, and nutrient processing remains "shallow" within the depth that nutrient migration and diffusion can occur.

So, fine grains may actually "limit" the depth, and therefore the Available surface area that aerobic bacterial populations can occupy.

Further, within our reef tanks, the reduced flow that is often times used to avoid sand storms, also reduces advection flow at the surface of the sand, and even worse, can in some cases, allow organic solids to remain in contact with the surface, where they are processed, and "sink".

Now comes the "composition" of the sand or substrate. Araganite has been highly "touted" over at least the last several years, as "the best" for "buffering substrates". True or not, I am not yet convinced that this buffering capacity is as high as we have been led to believe, and additives of some type are usually required.

The unfortunate thing is that substrates that "buffer", do so by dissolving, and the first consequence of this is that the already fine grains become "even finer". I think that there is plenty of evidence available to support the notion that finer grains that are dissolving are more prone to crystalizing and "clumping".

In some cases this crystalizing can be the result of pH fluctuations that are likely to occur as the result of mixing, siphoning, stirring, etc. Also, Araganite is purported to have a goodly bit of Phophate bound up in it to begin with, and this phosphate at whatever level it is present, is certainly released when the calcium and carbonate buffers are released.

So GEE, am I bashing sand beds here? ABSOLUTELY NOT !!!!

Still, whatever goes on in a sand bed is something, or should I say, many things, that we need to understand.

I am certainly not an expert on this by any stretch, but I have done a tremendous amount of research on the subject, and this thread is part of it.

Ok, what to do, if any of this is true? Well, again, my take on this is that the finest grains might be best avoided in the display tank, where we are looking for longevity and ease of maintanence. I'm only talking about the finer "mud" here ( up to .2mm ).

Also, some "fine gravel" ( .5 to 2mm ) at the surface, will certainly reduce any sand storm potential to the point of "managability". Up to an 1 1/2" depth of this seems good, then your finer sand underneath. I bounced this idea off of Anthony Calfo a while back, and he stated that it would not cause a problem to bacteria or "fauna" either.

Now of course, the "fauna" and other sand critters as well as sand animals will have their effect here as well, and this is quite impotant in my opinion, both for the health of the bed, and the sand animals themselves.

Still, I think we might want to restrict access of the larger animals to the top layer, and not have them mess so much with the finer denitrifying sand below. A critter screen of 4 to 6mm openings might accomplish this very well.

I do have this arrangement in my own tank, but it has only been operating for 11 mos. and so, cannot be used as an example of success. I have run well over 60 X flow with this arrangement, and without any sand-storm or other difficulty.

This is what I have learned and observed thus far, but that does not make it right or correct. I am here to learn more, just like everyone else.

Lots of great posting here, Thank you all!! > barryhc :)

[bertoni]

<a href=showthread.php?s=&postid=6453737#post6453737 target=_blank>Originally posted</a> by joefish

I would siphon anything that didn't look pure white and I stired the rest .

That's enough to kill a DSB right there.

4" is marginal, IMO. I went for 6". That does take up a lot of tank space, though. I'm not sure how many people want to buy (or have on hand) a tank that's an extra 6" to accomodate a sand bed.

The fact that removing the refugium seemed to help is also bizarre, and points to something strange happening, if the correlation is actually causal, which it might not be, either for the refugium or the DSB.

[bertoni]

<a href=showthread.php?s=&postid=6454792#post6454792 target=_blank>Originally posted</a> by chrismunn
lets say i have a 2+ year old DSB, and everything is well, but then one day while doing routine maintanence, i accidentally dig into the sand bed shifting a large portion of the sand, not only on top, but deep within the sand bed. have i then just ruined my DSB for any lenght of time (short , or long)?



You might disable part of the bed for some period if your maintenance kills off animals or pumps oxygen into the lower layers. The visible effects, if any, depend on a lot of factors. If the tank have a large macro-algae refugium, you might never notice. I'd avoid disrupting the sandbed, in general, but moving around rock has never been a problem for me.

[joefish]

<a href=showthread.php?s=&postid=6460783#post6460783 target=_blank>Originally posted</a> by bertoni
That's enough to kill a DSB right there.

.

After rereading where qouted me , that came out wrong .

If I saw any grey (detritus I would siphon that little area out . And when I said stired I ment just the surface so any detritus would be free floating .

Was that also bad ?:(

[bertoni]

Yes, really, it was most likely very bad.

I think that's another pitfall of DSB systems. When I have an algae problem, I have to live with it longer than I would with a SSB or DSB system. The idea behind them is to use more biology to solve problems, but biological systems work on their timescale, not ours.

Another issue here might be more fundamental. A DSB system is targeted at keeping more organisms alive. I think it's quite possible that problem algae are more likely to be removable or more easily removed from a BB system, where you can do manual maintenance to starve them out pretty rapidly. Same possibly with Aiptasia. This is only a thought that I'm throwing out, though.

[barryhc]

<a href=showthread.php?s=&postid=6461731#post6461731 target=_blank>Originally posted</a> by joefish
If I saw any grey (detritus I would siphon that little area out . And when I said stired I ment just the surface so any detritus would be free floating .

Was that also bad ?:(

Probably not that bad, although it is better handled with sand critters and higher flow. Don't do anything to the sand bed.

There are various methods of maintnence, and they are workable, but I prefer critters, flow, and do nothing to the sand bed.

Your tank was really beautiful, even with the algae, and still is as a BB. I don't know what the algae was or what, if any, critters would help to remove it, but I can't see how to call it a failure.

Good luck with the new one. > barryhc :)

[kbmdale]

ok so lets look at what barry said above

the norm is to get a fine sand and add 4" to the bottom of the tank. Now barry said that with the fine sand there is a shallower aerobic area. lets say the first 1", then there is a 3" anaerobic area underneith. Is it possable that 1" is not enough surface area to effectively filter, and will only supply a small amount of the anaerobic area. So back to what I said 2 pages ago.

What if you make a 5"->2"->5" dsb...the 5" area's at each end and the 2" in the middle. Then you are effectively adding surface area to the aerobic area which should equal out the same amount of anaerobic. Does this make sense. Like I said the DSB tanks I have seen longevity out of all seem to have high and low spots in the tank. Maybe there is a relationship to it whether it be by accident of by design.

[bertoni]

The low spots won't function as a DSB, IMO. So you're reducing the effective filtration area. Nothing wrong with that, but I don't see how it can help. The shallow areas should be more susceptible to nutrient buildup, if you believe the logic behind the deeper sandbeds.

[kbmdale]

why is that i wonder, i mean seems to me that it would make for a more equal distribution of oxygenated and non oxygenated areas in the dsb. which might make it more effeceint.

[kbmdale]

<a href=showthread.php?s=&postid=6452701#post6452701 target=_blank>Originally posted</a> by npaden
I guess my 4 1/2 year old high flow SPS dominated DSB tank is inappropriate then?

http://padens.com//tank_pics_10-2-05/images/fulltank_10-2-05_700.jpg

look at the levels of the sand in this tank. I have seen several others like it that have been successful in the long term of 3+ years. Your right could be nothing, but could be a clue easily overlooked.

[bertoni]

I'm not sure what you mean by more even distribution of oxygenated levels.

[kbmdale]

me either at this point, I think this cold is making me crazy...lol... I'm probably way off base.

[barryhc]

I think we need to look again at the "nitrification" and "denitrification cycles". Nitrification is performed predominantly in the upper level of a sand bed. The depth of this upper level is not well described in most literature regarding Marine Environments ( especially "captive reefs" ), and rightly so.

The effect of infauna ( the little guys ), and even more so of burrowing and sifting animals, has a huge effect on the depth of oxygenation, and without specific "animal-type-and-population" data, no depth of oxygenation can be predicted, or obviously specified.

Certain "recipes" have been given to the hobby, and touted as "the correct way" to set-up a sand bed. When strictly adhered to, these recipes can work quite well. Elsewise, who knows, and I doubt that these reccomendations have been followed all that closely by many aquarists.

Also, some of these "recipes" may work for a community tank, and might not be the best scenario for SPS dominated tanks, and as of recently, possibly "Dendros" as well.

Several of these recipes, specificly require that "sifting animals" are not allowed, much to my great dissatisfaction, and further, that burrowing animals will "destroy the functionality" of a deep sand bed, and again, I just can't swallow this restriction. I just don't think that it "has to be" the case.

So for nitrification, this occurs mostly in aerobic areas of the bed where nutrients are available for our familiar bacteria to process. Sifting and burrowing animals have the effect of keeping this area aerobic as well as avoiding "clumping" and keeping the surface "turned" so that algal mats of various kinds do not take over. Some of these also deplete the "infauna" population and this can be a detriment to the system depending on . . . .

Well, then the infauna help to bring dissolved nutrients into the sand bed for processing, and then help to export them when they are eaten, and then "up the chain" until poop is avilable in the water column for skimming or mechanical removal.

Denitrfication is far less well understood by a large portion of the reef keeping community. Very many aquarists still believe that denitrification occurs in the Anaerobic "zone" ( or areas ) of the sand bed, and this is really quite inaccurate. Many aquarists are well versed in this I realize, but many are not, and more so as we look not so far back in time.

The first and most recognized function of denitrification is the reduction of Nitrite into Nitrate and various other results. This process is carried out primarily in a very thin layer or space in the substrate depth.

It need not be vertical either, but it is described in most studies, as occuring in a "layer" as thin as .5mm between the aerobic and anaerobic zones, and "usually occuring at a depth of approx. 5 to 10 mm's deep in fine sediments that are not disturbed by sifting or burrowing animals".

This "zone" has been described with various terms by both hobbyists and experts alike, often times in contradictory fashion, in all directions, and has been the source of an unbelieveable amount of confusion. I know this for sure, from all the research I've done trying to understand it myself, and the only terms that are not confused in this regard, are "low oxygen", and "Hypoxic".

I like the "low oxygen" term myself, because you just can't confuse that term.

In the "low oxygen" environment, NON-OBLIGATE ( faculative ) Anaerobic bacteria are responsible for reducing Nitrite to Nitrate and other compounds, and this occurs in a ( usually ) very thin layer as stated before.

How thin is this layer actually, especially when "disturbed" or modified by sifting and burrowing animals? I don't know, after 14 mos. of investigation, I'm still trying to find out.

It is now below this "low oxygen" zone, that other processes are carried out by OBLIGATE Anaerobic bacteria, and it is here where Nitrates and other nutrients and compounds are processed into nitrogen gas supposedly, which is somewhat controversial for some reason, and hydrogen sulfide ( again contrversial ), Phosphates "bind and leach", heavy metals "sink", and again, guess what, all controversial.

I believe that all these processes occur in a deep sand bed, to one degree or another, and likely, different in every tank. It is the DIFFERENT in every tank part that has gotten us into this discussion, I'm sure, along with many other things.

I've gotten "long winded" again, not really intending to do so, sorry about that. And I'm no expert, but these again are my observations from very much research.

By the way, algal mats, "binding and leaching", clumping, "sinking", and sifting and burrowing critters, can all be dealt with using a bit of consideration IMO.

Any similar ( or not ) observations?

Happy Reef Keeping ! > barryhc :)

[Sindjin]

I think more research and emphasis needs to be focused on Phosphates in the DSB. Phosphates really dont get broken down...just pushed further into substrate... hence, like Bomber always said, that is why we have phosphate mines in Florida.
Yes, the DSB is a great addition to aid in denitrification but the storage of phosphates needs to be examined as I believe PO4 could be released slowly...causing algae blooms, etc.

I run a BB in my 120. And no.... I do NOT intend to change this thread to a DSB vs BB thread. A few weeks ago I used a turkey baster and sucked up a dime sized pile of detritus from the bottom. It accumulated ONE DAY after I siphoned the tank and changed some water. I placed that sample in a cup and immediately tested that sample for PO4. It read 3.0ppm. I then ran a general test of the water column which read .06ppm. This showed me that a brand new pile of debris emmitted a ton of PO4. Now...what would happen to it if I was running a DSB? It would have sunk into the bed where it would remain and build up.
Right? Im asking because this aspect of DSB reef keeping really hasn't been answered...at least from what I have read, and I would love to learn more about it.

[SDguy]

<a href=showthread.php?s=&postid=6466240#post6466240 target=_blank>Originally posted</a> by Sindjin
I This showed me that a brand new pile of debris emmitted a ton of PO4. Now...what would happen to it if I was running a DSB? It would have sunk into the bed where it would remain and build up.
Right? Im asking because this aspect of DSB reef keeping really hasn't been answered...at least from what I have read, and I would love to learn more about it.

I'm not sure about that. Isn't the idea to have enough flow to keep the presumably lighter-than-sand detritus up off the sandbed? I know I have my flow set to shoot down then over the sand..set just right to not make an empty hole in the back of the bed, but still flowing out over the bed, then back up. (Granted, this is much easier to do in a hex tank I think, due to it's shape).

Also, wouldn't well cured live rock (some might say cooked) help with this aspect...much less detritus shedding from rocks = less buildup, if any in the DSB = less or no chance of "leeching" phosphates.

What do you think?

[Amphiprionocellaris]

First, a thought about algae...
The presence of algae can't really be used (IMO) as a sign of DSB (or any system) failure. Algae is a natural part of the reef (as the zooxanthellae in your corals would tell you), and shouldn't really be considered a problem until it affects coral health (leaching, direct overgrowth, etc.). If it detracts from the appearance of the tank, it should be considered a nuisance, not a problem (very fine difference). There are, IMO, two primary reasons that algae does not totally dominate the natural reefs.
First, almost all the space is taken up by more efficient competitors (coral and coralline algae). That is why more northerly coral collections (not true reefs anymore) are [naturally] dominated by algae rather than coral: conditions are not as favorable for the coral, so the algae moves in.
Second, the reef has a much higher concentration of herbivores than our tanks. Granted, it can be very difficult to provide proper housing for a school of tangs (actually, "impossible" might be more appropriate). On the reef, algae is grazed before it can even grow to any great extent (hence the evolution of coralline algae, which is grazed only by a very small part of the herbivore population). The plethora of herbivores found on the reef is, to me, evidence that there is an intense amount of algal growth that is not apparent because the algae is so quickly consumed.
I think it is those two factors (lack of near-natural coral coverage and lack of herbivores) that lead primarily to algae problems in otherwise healthy tanks. Fixing these two factors can sometimes be difficult (it's hard to get 80% coral coverage in an algae dominated aquarium), but I think that's enough off-topic for now. My point is simply that algal growth shouldn't automatically be associated with DSB failure.

Now, onto DSBs. One thing that I think really makes or breaks a system is the ability of the natural infauna to survive. Because most home aquaria have very small sand areas (ie bottoms), they simply can't have large-enough sand beds to support the ecosystem. This leads to gradual die-off. This is easily circumvented by getting a "booster" for the infauna (unfortunately, I don't know off the top of my head where to get the starter packs). This also might be why larger systems seem to do better (more surface=more survivability of infauna). This [macroscopic] infauna is necessary for dealing with wastes other than nitrogen compounds. Thankfully, though, the nitrogen-processing bacteria tend to reach equilibrium fairly quickly, so that aspect of the DSB is never really compromised by faunal extinction.
That's certainly not the only factor, though. Increased water flow certainly helps (helps not just the DSB: it is more conducive to coral growth, see above about "algae"). Stirring shouldn't be necessary with healthy infauna, but it might become necessary. If you absolutely must stir, I think it's best to just stir small (very small) portions at a time, so as not to disrupt things to much. Healthy DSBs, though, need no stirring.

[barryhc]

<a href=showthread.php?s=&postid=6466240#post6466240 target=_blank>Originally posted</a> by Sindjin
I think more research and emphasis needs to be focused on Phosphates in the DSB.
I quite agree.

Phosphates really dont get broken down...just pushed further into substrate... hence, like Bomber always said, that is why we have phosphate mines in Florida.
Not convinced at all of this one.

Yes, the DSB is a great addition to aid in denitrification but the storage of phosphates needs to be examined as I believe PO4 could be released slowly...causing algae blooms, etc.
This is the good part. This is quite true, especially the "could be" part. It has happened before in sand beds I'm quite sure, and has caused the crash, or failure, or whatvever. The big point here though is, IMHO, that it IS NOT a "necessary eventuality".

I'm asking because this aspect of DSB reef keeping really hasn't been answered...at least from what I have read, and I would love to learn more about it.

We are trying to answer it here, and it won't happen in a few days, but if you are really interested in reading, try the two terribly long posts of mine on this page, and then comment. Maybe the whole thread for that matter.

Let's see where it takes us.

Happy Reef Keeping! > barryhc :)

[Sindjin]

Also, wouldn't well cured live rock (some might say cooked) help with this aspect...much less detritus shedding from rocks = less buildup, if any in the DSB = less or no chance of "leeching" phosphates.

Yes, Cooked rock would help prevent shedding and adding unwanted waiste to your tank. I have a tone of flow in my BB but I still get one small area where a pile accumulates. Im fine with that. When I did that experiment, what I actually siphoned out was snail poop. And yes, I have observed the process so I know it was mostly snail poop. :) But in a DSB, you cannot always have as much flow as you want due to sand storms. I think periodic stirring is a good idea. I also believe that more DSB enthusiasts should look into Rock Cooking to allow the Rock to shed as much detritus out of it as possible before placing on top of a new sandbed. That way you are more in control of added waistes into the tank. This control, IMO is more important in a DSB than a BB.

[Sindjin]

BarryHC,

I read your "long winded" post and read a lot about denitrification....but not much mentioned on PO4.
I would also like to mention that I agree... that PO4 leeching in a DSB is not a "neccessary eventuality" like you mentioned. I think that most tank crashes, failures, etc are from poor husbandry or equipment failure. However after so many years of tiny bits of waiste accumulating somewhere in the sandbed...you cant help but wonder. Thats why I mentioned my experiment: to show that brand new snail poop tested at 3.0ppm. One day old, too. Imagine years of that accumulating and being stored in a DSB. Please understand that I am not bashing DSB's... merely thinking about it and wanting to learn! :)

I guess we need to get into the chemistry of PO4 and its relation to the N cycle to fully understand. I know there were some links to some published papers floating around here somewhere.

[barryhc]

<a href=showthread.php?s=&postid=6466376#post6466376 target=_blank>Originally posted</a> by SDguy
I'm not sure about that. Isn't the idea to have enough flow to keep the presumably lighter-than-sand detritus up off the sandbed? I know I have my flow set to shoot down then over the sand..set just right to not make an empty hole in the back of the bed, but still flowing out over the bed, then back up. (Granted, this is much easier to do in a hex tank I think, due to it's shape).

All right, you caught me!!! :lol: :lol: Yes it is very easy to get this high flow in a hex tank, especially with the rock work elevated by a couple of inches, like it is in mine. Both are very important considerations in almost any reef setup in my opinion.

I think that aquascaping has been the culprit as well in many applications, as it hinders flow, and unreasonably shields sand beds from proper processing.

Also, wouldn't well cured live rock (some might say cooked) help with this aspect...much less detritus shedding from rocks = less buildup, if any in the DSB = less or no chance of "leeching" phosphates.

What do you think?

Probably true to some degree, well almost certainly, but I'm not convinced that the mineral portion of detritus is that much of a burden in sand beds. Some yes, but probably very much less than the organic portion of detritus which is lighter and easily kept swept up into the water column for skimming etc..

[Amphiprionocellaris]

The problem with phosphate is that it doesn't have this nice, neat little cycle like nitrogen compounds, that result in N2 bubbling out of the aquarium. It can be changed into various forms, but it's always still there. Preventing detritus from breaking down is a major help, but I highly doubt that 100% prevention is possible (DSB or BB).
In a healthy DSB, the infauna should take care of the phosphates (or at least help) by consuming the waste that would release it into the water. It's like on the reef: there are tons (literally) of nutrients in the reef ecosystem, but they're used up faster than they're produced.
That might be why many DSBs experience an algae bloom after a couple of years: the infauna start to die off, leaving nothing to take care of phosphate. The process of extinction takes about 2 years, which seems to be the same time frame for "crashes" (though, again, I don't think the mere presence of algae means a crash).
Just an idea...

[barryhc]

<a href=showthread.php?s=&postid=6466779#post6466779 target=_blank>Originally posted</a> by Sindjin
I guess we need to get into the chemistry of PO4 and its relation to the N cycle to fully understand. I know there were some links to some published papers floating around here somewhere.

I think you are quite right about this, but information that is directly applicable to the processes inside our reef tanks is exceedingly difficult to come by, and even the few that exist, are often times deeply flawed.

We certainly don't need to reread any estuarial studies, or other hobby related studies that are biased toward or against certain methods. I have read oodles of those until I'm sick, and we need some fresh unbiased material to chew on.

There was a tremendous lot of information in those posts I suggested, that explain about potential sand storms and why they needn't be a problem. Did you catch that part?

Thanks for posting here Sindjin, let's see what we can learn.

> barryhc :)

[barryhc]

Another thing that I have been trying to get at, is that some of the "recipes" that have been followed to some degree, by most sand bed aquarists, have been promoted by people who believe that duplicating the "natural condition", is the best approach. I doubt that can be done even with 35 acres of water. "Duplication" simply isn't possible.

I do believe that mimicking the natural conditions to a degree THAT IS HELPFUL, is an excellent idea, while avoiding certain aspects of the natural approach, may be equally important, and I would include skimming as a valuable approximation of the natural approach, by the way.

I remain concerned about "muds" especially, and extremely fine sands, as potentially to likely "problematic" to use in the display tank itself, in most instances.

You can do whatever "floats your boat" in a refugium.

> barryhc :)

[SDguy]

<a href=showthread.php?s=&postid=6466790#post6466790 target=_blank>Originally posted</a> by barryhc
All right, you caught me!!! :lol: :lol: Yes it is very easy to get this high flow in a hex tank, especially with the rock work elevated by a couple of inches, like it is in mine. Both are very important considerations in almost any reef setup in my opinion.



Hehe, that's funny...I was actually referring to my own tank :D

[barryhc]

<a href=showthread.php?s=&postid=6467373#post6467373 target=_blank>Originally posted</a> by SDguy
Hehe, that's funny...I was actually referring to my own tank :D

Yeah but, what about those extra 3 gallons. I was thinking of upgrading to a thirty, but I'm concerned about the extra volume. :p

Here is a nice link on particle sizes, and "fauna". Thanks "Guy".

http://www.wetwebmedia.com/deepsandbeds.htm

It sounds like a special grade of .5 to 1.5mm would be optimum at the surface, for gobies, cucumbers, and other "sifter-burrowers"( and maintaining high flow and detritus rejection ). I wonder if it's available already, I'll check it out.

Happy Reef Keeping! > barryhc :)

[SDguy]

<a href=showthread.php?s=&postid=6467942#post6467942 target=_blank>Originally posted</a> by barryhc
Yeah but, what about those extra 3 gallons. I was thinking of upgrading to a thirty, but I'm concerned about the extra volume. :p

Here is a nice link on particle sizes, and "fauna". Thanks "Guy".

http://www.wetwebmedia.com/deepsandbeds.htm

It sounds like a special grade of .5 to 1.5mm would be optimum at the surface, for gobies, cucumbers, and other "sifter-burrowers"( and maintaining high flow and detritus rejection ). I wonder if it's available already, I'll check it out.

Happy Reef Keeping! > barryhc :)

Thanks for the link. :) This I find humerous too. I posted that link in another thread one time, for someone asking about sand depth/grain size. Someone else chimed in with something to the effect of "that article is murky at best"...though they left it at that with no relevent followup information.:rolleyes: :rolleyes:

[barryhc]

I expect it stayed very "murky" as well, considering all the "mud" that he insisted was necessary in order to run a sand bed "ala-Shimek".

I suppose my reference to to "recipes" is just about hilarious now that I notice his having referenced "mud" with the consistency of "flour" as the dominant factor in the "recipe".

I think I'm starting to have trouble breathing. When I crawl up off the floor and find the keyboard, I'LL LET YOU KNOW!!!!

Happy Reef Keeping!! > barryhc :)

[SDguy]

<a href=showthread.php?s=&postid=6468300#post6468300 target=_blank>Originally posted</a> by barryhc
I expect it stayed very "murky" as well, considering all the "mud" that he insisted was necessary in order to run a sand bed "ala-Shimek".



:eek2: :eek2: Easy there...I actually don't rememebr who chimed in to my post...it was no one that I knew. :D

Anyways, I've been trying to nail down any sort of trend when it comes to algal blooms and DSB. But people seem to get them 1, 2, 3, 5, never years later. Phosphate leeching can apply to all these scenarios? My head hurts thinking of the other factors one would have to look at....fish load, food introduction, flow, etc. Can we even come close??

[Sindjin]

barryhc,

I did read thru your posts referring to utilizing various substrates to avoid sandstorms. Perhaps more engineering is involved in the proper setup of a DSB....with various layer barriers, etc.

I read thru a bit of this thread (http://www.reefcentral.com/forums/showthread.php?s=&threadid=725828&highlight=phosphates+sandbeds) . Dr Ron brought up some interesting points although some of it still seemed a bit biased. He mentioned that in an aquarium where there is a couple ppm of PO4, only a tiny percentage is actually bound to substrate. I could care less if the PO4 is bound to anything or not. All I know is that one day old snail poop emits a lot of PO4 (relative to the water column) and I want to remove it.... because so far, I dont know of any process that breaks it down. A while back, Bomber was mentioning something about bacteria utilizing PO4 during normal oxidation and denitrification processes... it was interesting...I'll try to look it up.

One final note... the aerobic and anaerobic processes that occur in a DSB also occurs inside our Live Rock so any factors we learn about PO4 in a DSB will also be very relevant to a BB.

See... we CAN all get along!
:)

So whats everyone's take on Cooking Rock for a DSB? So far IMO, it seems to be more of a BB thing but I think it is even more vital for a DSB.



Phosphate leeching can apply to all these scenarios?

Yes, PO4 can cause all those scenarios.
PO4 will be instantaneously released into the water column with waiste excretment. Nitrates, however is a by-product of the ammonia released from that waiste.

[SDguy]

<a href=showthread.php?s=&postid=6468424#post6468424 target=_blank>Originally posted</a> by Sindjin
Yes, PO4 can cause all those scenarios.
PO4 will be instantaneously released into the water column with waiste excretment. Nitrates, however is a by-product of the ammonia released from that waiste.

Right, I understand all that. I was more getting at the idea that it will be nice, though difficult, to know why different DSB leech at different times. For example, is it even possible for accumulation to have occurred to such an extent in these situations where the algal bloom is in the first two years? Does this come back to properly curing live rock, and the DSB just ends up being the improperly cured live rock's scape goat?? :D

So whats everyone's take on Cooking Rock for a DSB? So far IMO, it seems to be more of a BB thing but I think it is even more vital for a DSB.

I agree...though not to the point of cooking. Let's call it well cured :cool:

[Sindjin]

YES! Its all about the particular husbandry. If I set my tank up the way I read off of 3 different sites, I would have bought my live rock, put in my tank let it cycle for 2 or 3 weeks then removed it, put in 5" of sand and put the rock back in. Do you know how much crap my rock has spewed in the past 3 months? Tons... I couldnt imagine all that going into a new sandbed. No wonder so many experience algae blooms.

Thats why I believe in Cooking Rock...even though I didnt learn about this until after I set up my tank. All Rock Cooking is ....is Well Cured Live Rock that Cured in total darkness to kill off algaes.
Believe it or not, the process does not destroy all the life on the rock!

[barryhc]

<a href=showthread.php?s=&postid=6468335#post6468335 target=_blank>Originally posted</a> by SDguy

Anyways, I've been trying to nail down any sort of trend when it comes to algal blooms and DSB. But people seem to get them 1, 2, 3, 5, never years later. Phosphate leeching can apply to all these scenarios?

I don't see why not, since it would be a function of grain size, depth, flow, and most importantly feeding, mixed with the flow, and whether or not skimmng is being utilized, along with "how much bio-load". Most any time scale could apply, and aquarists have a tendency to try things out as well. Who's to say that the last "magic-bullet" didn't pan out, and the sand bed was to blame, rightly or wrongly?

Of course, algam blooms are not "strictly tied" to phosphate levels. Phosphate sure helps though.

My head hurts thinking of the other factors one would have to look at....fish load, food introduction, flow, etc. Can we even come close??

Sure we can, but is it going to happen next week or next month? That is what "they" thought 1,2,5,10,20 years ago. Was it true? then? Yes to some degree, but how close is close?

How about "closer"?

> barryhc :)

[Sindjin]

Every tank and every reef keeper is different, so many things are just NOT predictable due to many different variables.

[joefish]

<a href=showthread.php?s=&postid=6466386#post6466386 target=_blank>Originally posted</a> by Amphiprionocellaris
First, a thought about algae...
The presence of algae can't really be used (IMO) as a sign of DSB (or any system) failure. Algae is a natural part of the reef (as the zooxanthellae in your corals would tell you), and shouldn't really be considered a problem until it affects coral health (leaching, direct overgrowth, etc.). If it detracts from the appearance of the tank, it should be considered a nuisance, not a problem (very fine difference). There are, IMO, two primary reasons that algae does not totally dominate the natural reefs.


Algae is proof that all is not right . What does algae need to grow ?PO4 .;)

Now , If you don't mind seeing nuisance algae and the tank is geared twards soft Corals . Then you might be correct .

If you are geared more to Stony corals , they don't do well with PO4 present . SPS's realy does not like PO4 at all .

So nuisance algae is a sign of PO4 , and PO4 is bad . Then I would think that nuisance algae is a symtom of a worse problem .

[aubee91]

<a href=showthread.php?s=&postid=6468527#post6468527 target=_blank>Originally posted</a> by SDguy
Right, I understand all that. I was more getting at the idea that it will be nice, though difficult, to know why different DSB leech at different times. For example, is it even possible for accumulation to have occurred to such an extent in these situations where the algal bloom is in the first two years?

Is it possible that there are a couple of major mechanisms by which DSB's can work? It appears to me that DSB's as Dr. Ron wants them run are highly dependent on the infauna to work. I would assume that in this case (almost) all nitrates and phosphates are actually bound up in the bodies of the organisms living in the DSB themselves. I.e. worms eat snail poop and snails eat worm poop and smaller snails and worms eat their poop, etc. ad infinitum with the bacteria taking care of what little is left after all the critters get their share. In this case, not much denitrification would actually be occurring but rather nitrates (and phosphates) would be taken care of by the critters eating the nutrients.

In the case of a DSB that doesn't have a lot of infauna or critters, either because they weren't ever added or because they have died, denitrification by anaerobic bacteria is the main (or only) process occurring in the bed. And in this case the bed could or would work like Bomber and some others have proposed with the bed possibly eventually filing up and burping phosphate that has accumulated in the bed as a byproduct of bacterial denitrification.

Might this explain why some work and some don't and why some go for a long time and quit working while others quit working very soon? Feel free to dismiss this completely as I don't fully understand all the concepts and processes involved in this stuff. Which is why I'm reading this thread. :)

[barryhc]

<a href=showthread.php?s=&postid=6468424#post6468424 target=_blank>Originally posted</a> by Sindjin
barryhc,

I did read thru your posts referring to utilizing various substrates to avoid sandstorms. Perhaps more engineering is involved in the proper setup of a DSB....with various layer barriers, etc.

I read thru a bit of this thread (http://www.reefcentral.com/forums/showthread.php?s=&threadid=725828&highlight=phosphates+sandbeds)

Firstly I won't have anything to do with Shimek, Sihiya, or Komoyo.

Secondly, yes, I think so, but I could be wrong. I kind of doubt it, but well see.

A while back, Bomber was mentioning something about bacteria utilizing PO4 during normal oxidation and denitrification processes... it was interesting...I'll try to look it up.

This is true, and it does get complicated, but reef tanks are complicated. Those who claim that they are not are either simple minded, or have an agenda. I don't tolerate either one very well.

One final note... the aerobic and anaerobic processes that occur in a DSB also occurs inside our Live Rock so any factors we learn about PO4 in a DSB will also be very relevant to a BB.

You Betcha!!!!

See... we CAN all get along!
:)

Atta boy Sindjin!!!!!

So whats everyone's take on Cooking Rock for a DSB? So far IMO, it seems to be more of a BB thing but I think it is even more vital for a DSB.

I think that very many of the BB people are particularly into keeping SPS, and in some or even many cases, SPS are much more sensitive to Phophates than most other corals and animals.

They are driven to being obsessive, because some of the animals that they keep actually need the exceedingly nutrient poor conditions in order to survive. ( more so Phosphate, than Nitrate )

This apparently applies to nusiance algae as well, although I think it is really only a nusiance, and indicitave of nutrient levels, rather than actually detrimental to the corals.

Thanks again > barryhc :)

[SDguy]

<a href=showthread.php?s=&postid=6468735#post6468735 target=_blank>Originally posted</a> by aubee91
Is it possible that there are a couple of major mechanisms by which DSB's can work? It appears to me that DSB's as Dr. Ron wants them run are highly dependent on the infauna to work. I would assume that in this case (almost) all nitrates and phosphates are actually bound up in the bodies of the organisms living in the DSB themselves. I.e. worms eat snail poop and snails eat worm poop and smaller snails and worms eat their poop, etc. ad infinitum with the bacteria taking care of what little is left after all the critters get their share. In this case, not much denitrification would actually be occurring but rather nitrates (and phosphates) would be taken care of by the critters eating the nutrients.

In the case of a DSB that doesn't have a lot of infauna or critters, either because they weren't ever added or because they have died, denitrification by anaerobic bacteria is the main (or only) process occurring in the bed. And in this case the bed could or would work like Bomber and some others have proposed with the bed possibly eventually filing up and burping phosphate that has accumulated in the bed as a byproduct of bacterial denitrification.

Might this explain why some work and some don't and why some go for a long time and quit working while others quit working very soon? Feel free to dismiss this completely as I don't fully understand all the concepts and processes involved in this stuff. Which is why I'm reading this thread. :)

OK, so here's where it starts to get murky for me. We're talking phosphates...organic or inorganic? Then, there's the worry they are binding to the actual sand? Or are they still fixed to the detritus, which is in turn burried in the sand? Then another idea that they are in the living fauna found in the DSB? Are all of these true? Maybe this is the carrot that can lure Randy out of the chemistry forum to maybe shed a little light for me :D

[Acipenser]

I have some questions for Joe and the changes between his systems.

It looks from the before and after pictures that you added a lot of snails to your new BB tank. Is that true? I could not see really well in the first DSB tank picture. This in itself may have helped the algae problem.

Secondly, flow can not be overlooked in this situation. How much of an increase in gpm do you think you added to your new BB tank? SPS growth can be directly linked to flow. I had a frag in a DSB for about a year. I experienced a good deal of encrustation (about 2" all around the frag) but got no verticle or tip growth. I added another pump and the frag took off. No other changes but flow. I think your increased SPS growth might be primarily due to increased flow.

Also increased flow can increase coraline algae growth (which inhibits nuisance algae growth). Ever look at a tank that has a powerhead facing directly into the glass. It is usually a spot of significant coraline growth.

KBMDALE - This might also be the reasoning for the success in those DSB tanks that you mention have unlevel sand beds. this might be caused by the high flow rates in these tanks.

I think flow is often overlooked as one major factors in tank success.

Just my $0.02.

[joefish]

<a href=showthread.php?s=&postid=6469125#post6469125 target=_blank>Originally posted</a> by Acipenser
I have some questions for Joe and the changes between his systems.

It looks from the before and after pictures that you added a lot of snails to your new BB tank. Is that true? I could not see really well in the first DSB tank picture. This in itself may have helped the algae problem.
I was always adding snails. they kept dying off .The BB pics show them more and I had added some again too.

Secondly, flow can not be overlooked in this situation. How much of an increase in gpm do you think you added to your new BB tank? SPS growth can be directly linked to flow. I had a frag in a DSB for about a year. I experienced a good deal of encrustation (about 2" all around the frag) but got no verticle or tip growth. I added another pump and the frag took off. No other changes but flow. I think your increased SPS growth might be primarily due to increased flow.
Yes flow is a major issue people over look. I don't claim the change to BB was the whole reason for growth , But with less PO4 in the system I'm positive it was a contributer

Also increased flow can increase coraline algae growth (which inhibits nuisance algae growth). Ever look at a tank that has a powerhead facing directly into the glass. It is usually a spot of significant coraline growth.

KBMDALE - This might also be the reasoning for the success in those DSB tanks that you mention have unlevel sand beds. this might be caused by the high flow rates in these tanks.

I agree here , I think that is something overlooked .A good cause and effect.
I think flow is often overlooked as one major factors in tank success.

Just my $0.02.

[aubee91]

<a href=showthread.php?s=&postid=6468919#post6468919 target=_blank>Originally posted</a> by SDguy
OK, so here's where it starts to get murky for me. We're talking phosphates...organic or inorganic?

I'm not sure, but I would assume organic in this case since they would be entering the tank in/as food, but I don't know for sure.

Then, there's the worry they are binding to the actual sand? Or are they still fixed to the detritus, which is in turn burried in the sand? Then another idea that they are in the living fauna found in the DSB? Are all of these true? Maybe this is the carrot that can lure Randy out of the chemistry forum to maybe shed a little light for me :D

I have no idea if they are true. And a little light would be great. ;)

[barryhc]

<a href=showthread.php?s=&postid=6468527#post6468527 target=_blank>Originally posted</a> by SDguy
Right, I understand all that. I was more getting at the idea that it will be nice, though difficult, to know why different DSB leech at different times. For example, is it even possible for accumulation to have occurred to such an extent in these situations where the algal bloom is in the first two years? Does this come back to properly curing live rock, and the DSB just ends up being the improperly cured live rock's scape goat?? :D

I really don't think so, and here is where I have some "short-term" experience.

I had about 10 lbs. of base rock, and about 10 lbs. of live rock at the 2 mos. stage of my "little hex" aquarium. Cycling was over for the initial stage, and my nitrates were at about 100 ppm. I had bought some garf stuff, and it basicly just "killed the tank". Bad shipping maybe, I don't know.

I recieved my second batch of live rock ( about 25 lbs. ) at this point and proceeded to "cure it". I got the 16 gal. walmart tub, and put in the power head, the heater, and stuck 40 watts of PC lighting over the top of it 24/7 for 10 days.

Yeah I know, but I figured that if the stuff is going to grow, then just let it, and suck up the nutrients like crazy in the mean time. I can't say if I want to reccomend this, but this is what I did.

Now by a particularly strange coincidence, I had just recieved a shipment of "clean-up crew" from "Fosters and Smith", and for some reason they overshipped by about triple, so I ended up with about 40 snails and 40 crabs in this little tank, and having to figure out how to keep them from starving.

Then with the hair algae at about 1 1/2 to 2" long, I noticed that all those cool looking sponges were getting "covered-up", and not really knowing any better, I figured I had to "save them" somehow, so I decided to just give the food to the "detrivores".

I knew that this a bit out of the ordinary, with several fish and other animals in the tank , but hey, it's my little 27 gal. experiment, so why not just see what happens.

Knowing that the long hair algae was a huge bio-load, I took the smallest algae laden rock, and put it in the display tank to see what happened.

Lo and behold, 2 days later that rock did not have any algae on it. My ammonia was under 1ppm, and the nitrite was at zero, with nitrates at 120 ppm, and the fish and invertibrates didn't seem to mind at all, so in went another rock.

I can't really make the story shorter at this point, but in the interest of "brevity" I will say that 10 days later, 25 lbs. of new heavily algae laden rock was in the tank, and it was "cured". . . . . err, it didn't have any algae on it anymore.

I think the Nitrate got to about 140 ppm, and I did not have a Phosphate kit at that time, I'm sure it was exceedingly high.

So then I ran the tank for a while, and then converted the walmart tub to a make-shift refugium. Just an inch of old gravel, and a dead rock. The "dilution-solution".

I got some xenia after I got the Nitrate under 20 ppm, and added a couple more fish.

This is about the 5 mo. mark. Now here is the interesting thing , I ended up at 0 Nitrates at about the 8 month mark, I rarely change any water, and at the 10 mo. mark, Phosphate made it below .2 ppm.

At the 11 mo. mark, which is now, Phosphate is down to .05 to .1ppm, and I have quite a variety of softies, lps ,critters and fish. The several SPS frags, are not doing that well, as much from not enough light as the High Phosphate.

Now, I have a cucumber, 2 brittle stars, 2 shrimp, a moray eel, 20 crabs, 20 snails, 5 fish, zoos, open brain, torch coral, yada, and blah.

I also have a magnificent sea clone skimmer that I have to hold ever so dear to my heart. No other filtation.

I do not stir, I do not vacuum, or siphon, or else wise do any maintanence inside of the tank. Doh!, EDIT: I clean two panes of the glass, once a week, there isn't much there, or on the other four that I can't clean.

I do not have algae in the tank that you can see. I have only had a brief spell with cyano about 3 mos. ago in the refugium only, right after I fired up the refugium.

All the animals are happy, and I feed sparingly? about 1/2 teaspoon every day, mostly frozen and phytoplankton.

The substrate is as pristeen as the day I put it in, and grows a few pods, and feather dusters.

Do I have a Phosphate problem? Well at .1 ppm, maybe, but it is still on it's way down. So, if I have a problem in the substrate, from curing the rock, when am I going to see it?

I am being faciceous here, I don't have a phosphate build-up in the sand bed.

Could I end up with one, sure I could, but I won't let it happen.

I suppose if you just throw the live rock in there on top of the sand, and let it shed in an otherwise empty tank, it would be worse, but the bio-load and feeding are more important in the long term.

Geeze, shorten them up a bit heh? > barryhc :)

[Sindjin]

Barryhc,

Your experiment is interesting. Let me summarize my recent experience with my new 120, BB....just for kicks and giggles.
On 10/27/05, I put 100lbs of Fresh, UNCURED Fiji LR in my tank along with about 50lbs of base. Every few days I pulled out the rock, dunked/swished the rock in a seperate container of saltwater and changes about 25% of the tank water....while siphoning detritus off the bottom. I did this for 2 weeks. On 11/08/05 my Nitrates were at 40 ppm ...the highest they reached...and PO4 was at .4ppm. By 11/19/05, My Nitrates were at zero and that is where they stayed. My PO4 remianed at .4 for another month until they dropped where thay hover at about .04-.06ppm.

IMO, it was a pretty quick cycle considering I used Uncured Rock!

Could this because I did it in a BB? Meaning I was able to siphon out all the waiste that was accumulating....where as in a DSB it would have all sank into the bed....hopefully no one would cycle a new DSB with UNCURED Live rock but like I said... 3 sites/articles practically told me to do so.

If I were to set up a new tank with a DSB, I would Cook my rock seperately for 3 to 4 months. Then add the cooked rock on top of a new sand bed and start really slow.

[SDguy]

<a href=showthread.php?s=&postid=6469343#post6469343 target=_blank>Originally posted</a> by aubee91
I have no idea if they are true. And a little light would be great. ;)

Guess I should have checked the Chem forum first....here's a great read...

http://www.advancedaquarist.com/issues/sept2002/chem.htm

[inwall75]

This is a thread to read for anyone wanting to set up a DSB IMO.

I run DSB's and BB systems. One of my tanks could be considered to be a SSB system by some and a DSB by others...it all depends on our "definitions". For purposes of my post and not anyone elses, I will define 4" or greater to be DSB.

I've seen people get into arguments because their definitions of things are different so I thought that the best way to proceed would be to agree on what different things mean.

For some other definitions, let's hit the types of Phosphorus (P)

DIP--Dissolved Inorganic Phosphates
DOP--Dissolved Organic Phosphates
PIP--Particulate Inorganic Phosphates
POP--Particulate Organic Phosphates

This is a HIGHLY SIMPLIFIED EXPLANATION but this is MY definition unless someone has a better one (I don't want to get too technical so newer people don't freak out). Here's my thought.

Organic P--Is bound inside a critter, bacterium, or algae. Not testable by most hobbiest test kits.
Inorganic P--Is not bound inside a critter, bacterium, or algae but may be adsorbed to a Major component of NSW (I.e. Calcium-phosphate, Magnesium-phosphate, etc.) or unbound as PO4. Most of this is also not testable by hobbiest test kits unless it is unbound PO4.

Definitions from the thread previously discussed:

Crash = sudden deaths that occur fast .

Failed= not working right.

IMO, if this thread is going to be successful, everyone has to be on the same page so lets work out common definitions ahead of time.

[Weatherman]

<a href=showthread.php?s=&postid=6468580#post6468580 target=_blank>Originally posted</a> by Sindjin
All Rock Cooking is ....is Well Cured Live Rock that Cured in total darkness to kill off algaes.

Having once worked at the National Organization for the Advancement of Acronyms (NOAA), I think we need to find a catchy new acronym for rock cooking.

WCLRTCTDKOA is just too complicated. :D

[SDguy]

<a href=showthread.php?s=&postid=6469753#post6469753 target=_blank>Originally posted</a> by Sindjin
By 11/19/05, My Nitrates were at zero and that is where they stayed. My PO4 remianed at .4 for another month until they dropped where thay hover at about .04-.06ppm.

IMO, it was a pretty quick cycle considering I used Uncured Rock!



I have a question. How did you get your phosphates down in this time period. Since these are orthophosphates you are testing for, they are not skimmable, so siphoning detritus would not work. You either exported them, or they bound to something (ie LR). Am I correct in this thinking?

[Sindjin]

I have a question. How did you get your phosphates down in this time period. Since these are orthophosphates you are testing for, they are not skimmable, so siphoning detritus would not work. You either exported them, or they bound to something (ie LR). Am I correct in this thinking?

My best guess would be husbandry. I swished and dunked the LR a lot and continued to blow it off/out with a Turkey Baster. Then I siphoned a lot of detritus off the starboard bottom.

[gman0526]

Awesome thread guys keep it going!!! ;)

[Sindjin]

OOoo another thing... It was easy for me to blow out the rocks and then siphon the crap out of the tank...but if I had a DSB... I would have done the same process but in a seperate container, in total darkness AND a lot longer...

Im 3 months in and my rock is still shedding. I am a firm believer in cooking. :) I wish I did it! Then my tank would be pristine.

[Sindjin]

SDguy,

That was a great link/article about Phosphate in our tanks! Interesting that pH, Calcium and Alk have such a role.

[onthefly]

Since I've used both BB and DSB systems I'll chime in on a couple of observations.

1) Over the last few years, it seems alot of DSB's have been composed of uniform "oolic/southdown" types of beds (probably a cost issue since SD is so cheap!). It's my understanding that most of the DSB "experts" recommend a mixture of several types/sizes of sand. Could these uniform sized beds be "hastening" DSB failures?

2) As for stirring/vacuuming DSBs...and that being a "recipe for disaster". Steve Weast regularly siphons his sandbed (albeit the upper layers), removing sand in the process, and replacing it with fresh sand. So I see a couple things here that apply to this discussion: 1) by slowly using a remove/replace method.....he's avoiding any PO4 sink issues (if in fact that's the case), and 2) It would appear that vaccuuming a DSB is "not" a recipe for disaster.

[Sindjin]

I agree... If you begin your tank with light vaccuming your good... but if you decide to vacuum and stir up a 5 year old sandbed...watchout and be careful....you wouldnt want to release any nasty pockets.

I have not setup a DSB reef. BUT I spent the last 10+ years running freshwater Live Plant tanks. ...complete with a deep bed and DIY CO2 generators (yeast and sugar). Anyway... my substrate consisted of a mud layer, sand layer then a fine gravel layer on top. I would periodically siphon out the top gravel layers but would not disturb the other layers. Mostly due to the plant roots BUT also to not release nutrients. Hmmmmm not that DSB's of fine sand and mud are nutrient sinks. ;)

But in a DSB... if you maintained a decent critter count wouldn't they theoretically sift thru the sand? Besides... I do remember reading where a sand bed would be better left undisturbed as to not grind up your critter population.

[Weatherman]

<a href=showthread.php?s=&postid=6470822#post6470822 target=_blank>Originally posted</a> by onthefly
2) As for stirring/vacuuming DSBs...and that being a "recipe for disaster". Steve Weast regularly siphons his sandbed (albeit the upper layers), removing sand in the process, and replacing it with fresh sand. So I see a couple things here that apply to this discussion: 1) by slowly using a remove/replace method.....he's avoiding any PO4 sink issues (if in fact that's the case), and 2) It would appear that vaccuuming a DSB is "not" a recipe for disaster.

It appears likely that the purpose of the sand in Steve Weast's tank is for appearance only. There was no intent to set up a sand bed as a denitrifying filter.

If you want to take that route, you need to be willing to keep the sand bed dynamic (always stirred up, continuously removed and replaced).

[SDguy]

<a href=showthread.php?s=&postid=6470498#post6470498 target=_blank>Originally posted</a> by Sindjin
My best guess would be husbandry. I swished and dunked the LR a lot and continued to blow it off/out with a Turkey Baster. Then I siphoned a lot of detritus off the starboard bottom.

Hmmm, I also wonder how much impact this rock shedding has on the DSB as compared to, for example, all the food one would be adding to a tank with many fish...on a continual basis. I'm just not sure that, post standard curing, any more detritus will be worse than fish food (eventually poop) entering the system. Both should be handled with a correctly set up tank (skimmer, flow, etc.) But this is for the a cooking thread :D

As for some comments about stirring your sand...I agree that it depends on why you're setting it up. To keep fauna, a denitrification system, etc manual stirring is bad. Use snails at most. If the sand is purely for aesthetics, then, yes, keep it really stirred up and blowing in the flow :D In fact, this wouldn't even be a DSB anymore anyways. It shouldn't be as deep either.

[bertoni]

<a href=showthread.php?s=&postid=6471751#post6471751 target=_blank>Originally posted</a> by SDguy
Hmmm, I also wonder how much impact this rock shedding has on the DSB as compared to, for example, all the food one would be adding to a tank with many fish...on a continual basis.

I wouldn't "cook" (dark-cure) rock for a DSB. I'd just put the rock into the tank, and try to keep the animals, etc, alive. In a DSB, the focus is on using animals to process waste, etc. Perhaps with some care, the animals could be saved and the rock wouldn't shed as much. Otherwise, I'd just wait.

The whole issue of dark-curing seems irrelevant to me with respect to making a DSB work, anyway, so I consider far the whole issue off-topic.

One of the hardest parts of setting up a DSB is getting the right sand mix. I still don't have a handle on a good supply. None of the Carib Sea products are fine enough. Has anyone looked at the "flour" product to see how it stacks up?

[Sindjin]

The whole issue of dark-curing seems irrelevant to me with respect to making a DSB work, anyway, so I consider far the whole issue off-topic.

Thats just it... to me COOKING (dark curing) is even more essential in a DSB than a BB. It kills off all the algaes and allows bacteria from inside the rock to expell all the PO4. The critters you speak off to process waiste is the bacteria. Cooking the rock does NOT kill off this bacteria... nor does it kill all the "life" on the rock. Rocks will shed. The problem is we can't determine how much because we dont know what is actually built up inside it. Thas why to me it is vital for a DSB to have Rock that is a clean as possible.

[Acipenser]

Bertoni,

Firstly I won't have anything to do with Shimek, Sihiya, or Komoyo.

Care to elaborate? PM me if necessary.

Seems to me that they have a lot of information on the subject and to flatly reject their ideas seems a little irresponsible for this thread.

[inwall75]

I know I'm going against the grain here a little bit. I would suggest that aragonite sand would be the preferable sand over silica or other substrates for a NEW tank for reasons other than the smoothness that is commonly mentioned.

Here's my logic. Let's throw the spaghetti against the wall and see if it sticks.

Bacteria need phosphate to both live and to reproduce. When setting up a tank, we want a good bacterial population to perform nitrification and denitrification for us as soon as possible. Any aragonite sand you put in your tank is already going to have phosphates adsorbed to it whether it was mined or pulled out of the ocean. In other words, a limiting factor for bacterial life/growth/reproduction has already been provided. I would surmise that you can populate your sandbed quicker as a result.

Now obviously, using ANY kind of substrate will allow bacteria to grow. My thoughts above are simply related to the quickness of growing your bacterial population in your bed. I could be wrong...it just seems to make sense to me. If you are not in a hurry, I don't think it matters one way nor the other.

Here's some background for newbies. Bacteria populations are rather dynamic. If there is additional "food" for them to expand, they will do so and they will do it quickly. That's because they have a number of ways of reproduction and their populations grow exponentially. I.e. 1 bacterium becomes 2. 2 become 4, 4 become 8, 8 become 16, etc. Different species of bacteria can do this over varying periods of time but many species can do this over a period of a half hour or so. (BTW...the example I gave above is actually wrong but I don't want to go into logarithm's. The example above should at least give you an idea). If you find that you seek additional info on bacteria, here's a great "Bacteria for Dummies" link. http://www.bact.wisc.edu/Microtextbook/modules.php?op=modload&name=Sections&file=index&req=viewarticle&artid=9&page=1

[Amphiprionocellaris]

<a href=showthread.php?s=&postid=6468650#post6468650 target=_blank>Originally posted</a> by joefish
Algae is proof that all is not right . What does algae need to grow ?PO4 .;)

Now , If you don't mind seeing nuisance algae and the tank is geared twards soft Corals . Then you might be correct .

If you are geared more to Stony corals , they don't do well with PO4 present . SPS's realy does not like PO4 at all .

So nuisance algae is a sign of PO4 , and PO4 is bad . Then I would think that nuisance algae is a symtom of a worse problem .
I only partially agree. I wasn't talking about a tank-consuming bloom of algae; that is indeed a sign of a problem. I was talking about little blooms of algae; say, a little hair algae in a corner of the tank. It's a sign of phosphate, but the phosphate is locked up in the algae, rather than being in the water column where it can do harm (one principle of a refugium). Perhaps that phosphate came from waste that didn't make it into an area where it could be processed. All I'm saying is that algae (small blooms that affect aesthetics, not the big ones that kill stuff) shouldn't automatically be considered a sign of a bad DSB. Algae can be, and often is, a product of a bad sand bed, but not all algae comes from having a bad bed.

[Sindjin]

Algae can be, and often is, a product of a bad sand bed, but not all algae comes from having a bad bed.

I agree. You can have hair algae growing on one spot on one piece of Live Rock because there is detritus being spewed out of the rock from that one spot. The undeterminable factor is the reason why so many are beginning to see the benefits of cooking rock.... to hopefully assure the fact that no algae will be introduced to the tank....and that the live rock will be completely shed of internal detritus. It just gives the Reefer that much more control.

[kbmdale]

Rather than cooking LR, wouldn't a better alternative for a new set-up be to use base rock. There is no life of saturation to contend with, then over time it becomes LR.

[inwall75]

<a href=showthread.php?s=&postid=6473975#post6473975 target=_blank>Originally posted</a> by kbmdale
Rather than cooking LR, wouldn't a better alternative for a new set-up be to use base rock. There is no life of saturation to contend with, then over time it becomes LR.

I don't think so. LR already has a lot of bacteria to begin with so your off to a better start, has less phosphates than mined rock, has some other critters that are interesting to look at. If cured properly, the dieoff that occurs due to transportation won't be an issue when added to your tank.

[kbmdale]

But by the time your rock cooks, my dead base rock will have been seeded with all the life that your cooked rock will come out of the cooking bin with...

[Amphiprionocellaris]

If a new set-up uses only base rock, where is the life going to come from? If you seed it with other live rock, oftentimes, the first thing to colonize the dead rock is microalgae, though that is often shoved out of the way by other life. There's really no substitute for well-cured live rock. How much and how you cure the rock are subjects that can be [and are] debated, but IMO, they all beat base rock (especially considering that base rock is usually a lot less porous than natural live rock).

[kbmdale]

For instance, I started a set-up with 10lbs of LR and 40lbs of dry base rock.. After 6 weeks you could tell no difference. As far as the base rock being less porous, I disagree..Its the same rock just dead..Or at my lfs it is. Now I can't speak of TBS or the really really good quality LR, I haven't found any that quality around here. But in May when I take the trip to FT. Myers for the in-law visit/vacation I will stop by TBS and pick up some of thier rock.

[King-Kong]

<a href=showthread.php?s=&postid=6474112#post6474112 target=_blank>Originally posted</a> by kbmdale
But by the time your rock cooks, my dead base rock will have been seeded with all the life that your cooked rock will come out of the cooking bin with...


This deserves more attention.

On many levels base rock is more environmentally responsible, cheaper, and (if its a reasonable expectation) it isnt packed with dead organics, then it is also an alternative to cooking large amounts of rock.

When I setup my 90g, I used about 20lb of cured (year old in my 20g) rock, and the rest was all base rock. It's been 3 months now, and the base rock (certain areas that are properly lit, receiving proper flow) is covered by corraline (50%++)

I cant even defend buying all live rock anymore. I will never again do it, and will maintain a 25%/75% ratio for the future.

If we're only introducing small amounts of live rock to our tanks, then cooking may not be as important, or cooking would be easier, as we have less rock to work on.

[Sindjin]

I used 50lbs of base rock from reeferrocks.com. It was really nice, porous rock.... I would reccomend it! It still had a lot of debris inside it....even though it was dead rock. So even if you set up a new tank with Base Rock, I would still put it thru a cleaning process...it will just take a lot less time than Cooking Live Rock.
If you Cook Live Rock, you will end up with well cured rock, algae free and still full of life. Pods, Crabs, Snails, TubeWorms, etc have all been reported to survive 3 to 6 months of Cooking.

It would be nice to establish a NEW tank with brand new sand (if you want DSB) and clean base rock. Then you KNOW that from the very beginning you were in total control! :)


EDIT: I agree with King-Kong's post. Just seed the reef with Live Rock.

[barryhc]

<a href=showthread.php?s=&postid=6473690#post6473690 target=_blank>Originally posted</a> by inwall75
I know I'm going against the grain here a little bit. I would suggest that aragonite sand would be the preferable sand over silica or other substrates for a NEW tank for reasons other than the smoothness that is commonly mentioned.

I realize that silica is frowned upon in some cases because of "potential" diatom blooms. I'm not particularly convinced, but of more importance, to me anyway, would be the smoothness.

Is silica that harmful to the animals, and if so, are there alternatives, that are available down to .1 or .2mm?

I still don't care for the idea of "mud" and "flour-szed" substrate in the display, for reasons of clumping, PO4 release, and poor diffusion charachteristics.

Fine in the refugium, if you like, but what is the "need" for these ultra fine particles in the display sand bed?

Does the "food chain" break down significantly, or entirely, if particles smaller than .1 mm are not used in the bed?

Thanks all, > barryhc :)

[Sindjin]

I still don't care for the idea of "mud" and "flour-szed" substrate in the display, for reasons of clumping, PO4 release, and poor diffusion charachteristics.

I agree... like I said the mud thing reminds me of substrates I established in my FW plant tanks to PURPOSELY enhance the nutrient bed for plant growth. A lot about REEF DSB's remind me of that. i would focus more on granule size and sand-bed critter management.

[npaden]

I have 100% southdown fine grain sand in my display and don't have issues with sand storms unless something is wrong. The sand can shift a bit and move but it tends to stay on the bottom of the tank.

The issue with fine sand over coarse sand it it's ability to trap detritus IME. Detritus will sit on top of the fine grained sand but be trapped in the coarse sand. Also with the fine grained sand the aerobic area is not as large as with coarse sand.

FWIW, Nathan

[npaden]

Also, on the rock cooking issue. I cured my rock in my display with a brand new sandbed. It was the "plant rock" from walt smith and I worked out a deal where it was drop shipped to me directly with a person at LAX just relabeling the address and sending it on the next flight out to me. This rock arrived fresh from the ocean and was about 36 hours of transit time with wet newspapers and plastic bags. At the time walt smith left the plant rock in the ocean until time to ship and then pulled it out and packaged it with none of the "precuring" techniques. Other than dealing with a lot of sargassum growth at the start (which probably consumed any nutrients that were released from the rocks) I haven't had any issues with not "cooking" my rocks.

I also didn't jam pack my tank with rocks, I cured about 200lbs of rock in my 415g tank this way in 3 separate batches so I never had an ammonia or nitrite or even a nitrate spike that was measurable. I moved about 125lbs of rock from my existing tank after everything was up and running for a few months. Some of the rock that I have I got used from a tank that was completely covered in hair algae (I did scrub the rock with a toothbrush and dunked it in a bucket of tank water when I got the rock to clean the algae off of it) and that rock is getting close to 10 years old and has never been "cooked" and has no algae issues that I've noticed.

Just another opinion on rock cooking.

FWIW, Nathan

[barryhc]

Good old Capt. Jer from reeferrocks. That is where my live rock came from too. Very nice stuff!! This is the stuff that I cured "unconventionaly" in the display tank.

I wouldn't do it again that way, but I have suffered no ill effects "thus far".

I'll probably go to reeferrocks again for the large tank that is "under construction". I agree with the 25% live rock formula, although I'll have to search a bit for the base rock. Carib Sea has some real nice stuff, but I haven't checked the price yet.

I have been considering making some aragacrete, but I'm not sure of it's long-term charachteristics.

The next time I "cure", I'll probably do it the same way, with crabs and snails and lights on 24/7, but not over the sand bed.

Happy Reef Keeping! > barryhc :)

[Sindjin]

When I recieved my 100lbs of Rock from Walt smith, I kept blowing it out with a Turkey Baster to aid in the shedding.


Npaden,
Smart move on establishing it slowly, too.... Im sure that helped a lot!

[aubee91]

<a href=showthread.php?s=&postid=6472481#post6472481 target=_blank>Originally posted</a> by bertoni
I wouldn't "cook" (dark-cure) rock for a DSB. I'd just put the rock into the tank, and try to keep the animals, etc, alive. In a DSB, the focus is on using animals to process waste, etc. Perhaps with some care, the animals could be saved and the rock wouldn't shed as much. Otherwise, I'd just wait.


But IIRC, Dr. Ron says that the fauna on live rocks won't
populate the DSB anyway as they are not benthic. If so, seems like the critters on the live rock wouldn't be useful for DSB waste processing anyway.

[inwall75]

If silica sand would dissolve enough to cause diatom blooms on your bed, then you would have diatoms on your glass and silicone seams as well. All it means is that you have silica in your system as well as phosphates.

Calcite and aragonite have the same chemical composition....CaCO3. However, there is a HUGE difference in solubility. I've used "sandblasters" sand before with no apparent problem.

I've had sandbeds with ESV sand which is pretty darn close to flour. I've have sandbeds with much larger particles. I've had sandbeds that were mixed. Frankly, if you want to exploit particle size to control bacteria (somewhat), there are ways to do it. However, if anyone thinks that bacteria are not going to do what they need to survive because they don't like larger grains, then they need to stop and think a bit and stop reading. There are innate drives in critters and eating and surviving and reproducing. The whole "requiring" a certain grain size is a fallacy IMO.

[npaden]

As a tip, in my realy high flow areas that have a hard time keeping sand in place, instead of putting larger grained sand there or crushed coral I put some types of rubble there. Empty snail shells, small pieces of live rock, etc. This seems to be pretty effective in keeping the sand in place without it becoming a detritus trap.

FWIW, Nathan

[aubee91]

<a href=showthread.php?s=&postid=6474206#post6474206 target=_blank>Originally posted</a> by barryhc
I realize that silica is frowned upon in some cases because of "potential" diatom blooms. I'm not particularly convinced, but of more importance, to me anyway, would be the smoothness.

Is silica that harmful to the animals, and if so, are there alternatives, that are available down to .1 or .2mm?


I gotta ask this question. Why is important that the animals survive? Theoretically, aren't DSB's supposed to work by allowing denitrification to occur deep within the bed? Wouldn't it be okay to have a totally sterile aerobic layer (at least as far as infauna go) which gets stirred by stars, conchs, other large critters. At least theoretically shouldn't this work just fine? This is the idea behind the "DSB in a bucket" discussion from Anthony's forum, right?

This is why I asked the earlier question about whether the infauna or critters said to be necessary in a properly functioning DSB are actually doing practically all the work instead of the aforementioned denitrification in the lower areas.

Thoughts?

[onthefly]

Silicate IS NOT Silica. Chemically different.

Silicates cause diatoms....silica is glass!

One benefit (sort of) of silica over aragonite.....silca based sand beds won't solidify like aragonite will under certain conditions.

[aubee91]

<a href=showthread.php?s=&postid=6474179#post6474179 target=_blank>Originally posted</a> by kbmdale
For instance, I started a set-up with 10lbs of LR and 40lbs of dry base rock.. After 6 weeks you could tell no difference. As far as the base rock being less porous, I disagree..Its the same rock just dead..Or at my lfs it is. Now I can't speak of TBS or the really really good quality LR, I haven't found any that quality around here. But in May when I take the trip to FT. Myers for the in-law visit/vacation I will stop by TBS and pick up some of thier rock.

What kind of base rock did you use, Kris? I used reef bones and as far as I can tell they are just live rock that has been dried out as about half of them appeared to be just calcified coral skeletons. They even had purple on them from dead coralline.

[inwall75]

<a href=showthread.php?s=&postid=6474398#post6474398 target=_blank>Originally posted</a> by aubee91
But IIRC, Dr. Ron says that the fauna on live rocks won't
populate the DSB anyway as they are not benthic. If so, seems like the critters on the live rock wouldn't be useful for DSB waste processing anyway.

I've had numerous polychaetes that live in my rock migrate to my sandbed. I've had Nemerteans live in my sand. (Actually that's not a good thing but they also came from my LR). I've had what is commonly called spaghetti worms migrate to my sand.

[aubee91]

<a href=showthread.php?s=&postid=6474516#post6474516 target=_blank>Originally posted</a> by inwall75
I've had numerous polychaetes that live in my rock migrate to my sandbed. I've had Nemerteans live in my sand. (Actually that's not a good thing but they also came from my LR). I've had what is commonly called spaghetti worms migrate to my sand.

So at least some of the live rock fauna is at least "part time" benthic and live rock is useful in seeding the DSB.

[barryhc]

<a href=showthread.php?s=&postid=6474398#post6474398 target=_blank>Originally posted</a> by aubee91
But IIRC, Dr. Ron says that the fauna on live rocks won't
populate the DSB anyway as they are not benthic. If so, seems like the critters on the live rock wouldn't be useful for DSB waste processing anyway.

This can't be true, and I'll tell you why I think so. I have micro stars that were in my sand that go back and forth from sand to rock, and this includes as high up as 18" on the rock. The same is true of bristle worms, copepods, and other little critters.

I can't believe that these animals would somehow be much more "selective" in the wild.

What's up? > barryhc :)

[inwall75]

<a href=showthread.php?s=&postid=6474486#post6474486 target=_blank>Originally posted</a> by aubee91
I gotta ask this question. Why is important that the animals survive? Theoretically, aren't DSB's supposed to work by allowing denitrification to occur deep within the bed? Wouldn't it be okay to have a totally sterile aerobic layer (at least as far as infauna go) which gets stirred by stars, conchs, other large critters. At least theoretically shouldn't this work just fine? This is the idea behind the "DSB in a bucket" discussion from Anthony's forum, right?

This is why I asked the earlier question about whether the infauna or critters said to be necessary in a properly functioning DSB are actually doing practically all the work instead of the aforementioned denitrification in the lower areas.

Thoughts?

Aubee,

Critters help with bioturbation because a bed is less efficient working with only diffusion. Will it work....you betcha. Is it more efficient with bioturbation...you betcha.

[inwall75]

<a href=showthread.php?s=&postid=6474496#post6474496 target=_blank>Originally posted</a> by onthefly
Silicate IS NOT Silica. Chemically different.

Silicates cause diatoms....silica is glass!

One benefit (sort of) of silica over aragonite.....silca based sand beds won't solidify like aragonite will under certain conditions.

Quite true. I'm trying to not get too technical so that people new to the hobby aren't scared away. Maybe it is a mistake for me to do this but only time will tell.

You have to make a pretty big mistake to make aragonite turn into a brick. However, it can and has been done before.

BTW.....I realize that I didn't mention that sandblaster's sand is silicate sand.

[barryhc]

<a href=showthread.php?s=&postid=6474486#post6474486 target=_blank>Originally posted</a> by aubee91
I gotta ask this question. Why is important that the animals survive? Theoretically, aren't DSB's supposed to work by allowing denitrification to occur deep within the bed? Wouldn't it be okay to have a totally sterile aerobic layer (at least as far as infauna go) which gets stirred by stars, conchs, other large critters. At least theoretically shouldn't this work just fine? This is the idea behind the "DSB in a bucket" discussion from Anthony's forum, right?

Well, I can't say if it is right or not, but it is the kind of information that I'm looking for, so you kind of "hit the nail right on the head".

I'll have to reread that discussion. Can you give us the link in your next post?

This is why I asked the earlier question about whether the infauna or critters said to be necessary in a properly functioning DSB are actually doing practically all the work instead of the aforementioned denitrification in the lower areas.

Thoughts?

I'm pretty sure that the inhauna, or at least some of them, are travelling verticaly in the substrate, and this moves both nutrients and oxygen, deeper into the bed.

That having been said, it could be that the denitrification would still occur without them, but likely not nearly so effectively, and then there is the "clumping" as well, that they are supposed to help mitigate.

Good questions!! > barryhc :) :)

ooPS: You type too fast Curt !!!! :lol: :lol:

[KAiNE]

<a href=showthread.php?s=&postid=6474338#post6474338 target=_blank>Originally posted</a> by npaden
Also, on the rock cooking issue. I cured my rock in my display with a brand new sandbed. It was the "plant rock" from walt smith and I worked out a deal where it was drop shipped to me directly with a person at LAX just relabeling the address and sending it on the next flight out to me. This rock arrived fresh from the ocean and was about 36 hours of transit time with wet newspapers and plastic bags. At the time walt smith left the plant rock in the ocean until time to ship and then pulled it out and packaged it with none of the "precuring" techniques. Other than dealing with a lot of sargassum growth at the start (which probably consumed any nutrients that were released from the rocks) I haven't had any issues with not "cooking" my rocks.

I also didn't jam pack my tank with rocks, I cured about 200lbs of rock in my 415g tank this way in 3 separate batches so I never had an ammonia or nitrite or even a nitrate spike that was measurable. I moved about 125lbs of rock from my existing tank after everything was up and running for a few months. Some of the rock that I have I got used from a tank that was completely covered in hair algae (I did scrub the rock with a toothbrush and dunked it in a bucket of tank water when I got the rock to clean the algae off of it) and that rock is getting close to 10 years old and has never been "cooked" and has no algae issues that I've noticed.

Just another opinion on rock cooking.

FWIW, Nathan

I got the same rock for WS. It reminds me of the way quality LR used to be. I also got 88lbs of Tonga but IMO it wasn’t worth it. The Fiji "natural" as WS calls it is nice stuff, its packed far wetter than other rock. Starting with high quality biodiverse (sp?) LR is key IMO.

I feel most issues come down to IN vs. OUT. What goes in must come out at some point. If you can achieve a balance between nutrient imports and exports you will be successful.

-Chris

[aubee91]

<a href=showthread.php?s=&postid=6474573#post6474573 target=_blank>Originally posted</a> by inwall75
Aubee,

Critters help with bioturbation because a bed is less efficient working with only diffusion. Will it work....you betcha. Is it more efficient with bioturbation...you betcha.

Okay, I'm unfamiliar with the difference between bioturbation and just frequent stirring. This bioturbation only occurs in the aerobic portion of the bed, right? So what is it about the bioturbation that increases the efficiency compared to frequent stirring by larger critters? Is it simply because there are so many of the smaller critters and they just turn the grains over more frequently on average?

[aubee91]

<a href=showthread.php?s=&postid=6474641#post6474641 target=_blank>Originally posted</a> by barryhc
Well, I can't say if it is right or not, but it is the kind of information that I'm looking for, so you kind of "hit the nail right on the head".

I'll have to reread that discussion. Can you give us the link in your next post?


Here's the thread. Be forewarned that it's pretty long.

http://www.reefcentral.com/forums/showthread.php?threadid=595109

[Amphiprionocellaris]

<a href=showthread.php?s=&postid=6474201#post6474201 target=_blank>Originally posted</a> by Sindjin
I used 50lbs of base rock from reeferrocks.com. It was really nice, porous rock.... I would reccomend it!
Your base rock is a lot nicer than the stuff we get in at the LFS. It's a terrestrial limestone that has close to zero porosity. The stuff you're describing sounds like it's much better for a reef tank.

Just because no one else has done one, here's a sum-up of what I think I've taken from this thread (or as a starter for new discussion points):

1) Good curing of liverock (cooking or some other good mode of curing) is essential for a healthy, non-nutrient-loaded DSB. We pretty much have a consensus on that. We still appear to be undecided on the mode of curing (as well as LR composition, base vs. natural), but there appear to be many that work.

2) Particle size is important, but undecided. So far, a lot of people seem to avoid using the extremely fine sands, but there doesn't appear to be any real downside to very fine ones except for the potential for sandstorms. On that note, sandstorms seem to be easily avoided with some good planning (personal note to retailers: do not put gobies in sand tanks unless you want to play the "catch me in one minute or you won't be able to see me" game). There does seem to be a consensus that finer is better than coarse, due to the potential for nutrient traps (personally, I'm seeing one of those "moderation is key" scenarios, with the best results coming from mixed grades between the two extremes).

3) There are interesting thoughts on sand composition. It appears that (surprise, surprise) the different compositions (silica-based, calcite, aragonite) have distinct advantages and disadvantages. It also seems that they can all work with due planning (I prefer aragonite, but, having not tried the others, I can't really comment on them). There seems to be a fair consensus that mud would be less preferable, due to the fact that such mud is often used (but not always) when more nutrients are required. Again, I can't comment on that, not having tried mud.

4) There is a general idea of bed depth, with the minimum around 3"-4" (with more emphasis on he thicker 4"), but there is not quite a general consensus. There are also some interesting ideas with uniform vs. varied thickness, again with both providing good results.

5) A lot of DSB "crashes" (quotes used because there is not quite a consensus on the meaning of that term) occur around 1-2 years of age. Personally, I think this is because of fanual extinctions and the concurrent loss of waste-processing ability, though I have no experimental data to back that up (there are, however, studies that have shown extinction around 2 years; they just haven't related that to processing ability). Of course, as this is the subject of the discussion, we most certainly have not arrived at a conclusion on this point (why DSBs fail at times). Personally, I think it will end up being a combination of many factors, including [but not limited to] faunal extinction and use of improperly cured live rock.

OK, I think that's where we are in the "DSB optimization" discussion. Please correct me in the likely event that I have forgotten something or been in error. I hope everyone else has found this discussion as enjoyable as I have.

[inwall75]

<a href=showthread.php?s=&postid=6474678#post6474678 target=_blank>Originally posted</a> by aubee91
Okay, I'm unfamiliar with the difference between bioturbation and just frequent stirring. This bioturbation only occurs in the aerobic portion of the bed, right? So what is it about the bioturbation that increases the efficiency compared to frequent stirring by larger critters? Is it simply because ther are so many of the smaller critters and they just turn the grains over more frequently on average?

Bioturbation is basically the mixing/turning over of sediments....what is typically called sand-stirring. It helps move water and it's wastes around. There are some critters who will go to the anaerobic portion of the bed but not many. Basically, the denitrification is NOT occurring in the anaerobic section of your sandbed...it is occurring at the anoxic interface. The more water you can get to this anoxic interface, the more efficient your bed is at denitrification.

On a newer bed, this anoxic interface is much deeper than on an older bed. Other critters are quite helpful then. On an older bed, you might be fine with critters that don't go too deep. EDIT: But will it still work without them? Yes.

[barryhc]

<a href=showthread.php?s=&postid=6474620#post6474620 target=_blank>Originally posted</a> by inwall75
You have to make a pretty big mistake to make aragonite turn into a brick. However, it can and has been done before.

Doesn't the particle size have some effect on this, especially if you disturb the sand quite often by stirring, etc., which causes large pH fluctuations, and affects the "adsorption VS release"
of phosphate as well?

BTW.....I realize that I didn't mention that sandblaster's sand is silicate sand.

Posted by onthefly:
--------------------------------------------------------
Silicate IS NOT Silica. Chemically different.

Silicates cause diatoms....silica is glass!
--------------------------------------------------------

So is it Silicate sand, or Silica sand?

Thanks > barryhc

[Weatherman]

Here are some examples of silicate minerals:

Silicates (metal + Si and O)

quartz (SiO2),
potassium feldspar (KAlSi3O8),
Ca Plagioclase feldspar (CaAl2Si2O8),
Na Plagioclase feldspar (NaAlSi3O8)


http://mineral.galleries.com/minerals/silicate/class.htm

[barryhc]

<a href=showthread.php?s=&postid=6474678#post6474678 target=_blank>Originally posted</a> by aubee91
Is it simply because there are so many of the smaller critters and they just turn the grains over more frequently on average?

I think that is one of the big advantages, and it is particularly useful in avoiding clumping. Also, however, the infauna "eat", and then they are eaten. Eventually they get turned into fish poop, which is highly skimmable, and represents a net export.

Thanks again! > barryhc :)

[inwall75]

LOL....I'm going to quit taking shortcuts in my explanations.

Si is on the periodic table. Any variation would not be Silicon. I tend to use variations of it (as I do with many other elements) as one to keep things simple.

[kbmdale]

Silica sand....Its funny when it comes to sand that the hobby veiws silica as BAD...But when it comes to tanks no one seems to care that the glass and seal is made of the same thing...

[kbmdale]

<a href=showthread.php?s=&postid=6474913#post6474913 target=_blank>Originally posted</a> by inwall75
LOL....I'm going to quit taking shortcuts in my explanations.

shortcuts are only good for one thing, GETTING LOST..lol...everytime I try a short cut , I get lost... :lol:

[Acipenser]

I gotta ask this question. Why is important that the animals survive? Theoretically, aren't DSB's supposed to work by allowing denitrification to occur deep within the bed? Wouldn't it be okay to have a totally sterile aerobic layer (at least as far as infauna go) which gets stirred by stars, conchs, other large critters. At least theoretically shouldn't this work just fine? This is the idea behind the "DSB in a bucket" discussion from Anthony's forum, right?

I think there are two differing view points on this factor.

In my readings it seems that Calfo believes that in our reef systems our DSBs typically do not support the infaunal populations at levels that are necessary, based on our stocking the tank with creatures that eat the infauna. His use of a DSB in a bucket uses flow and mechanical filtration to prevent the accumulation of detritus in the sediment of the bucket, and uses the normal denitrification process of the bateria to reduce nitrates. More of a combined mechanical and bacterial approach.

Dr. Ron believes that DSB can be constructed to maintain sufficient populations of infauna. In this approach, detritus is processed by the various size creatures to eliminate as much nitrogenous waste as possible before bacterial processing. Then the normal denitrification process of the bateria in the sandbed is used to process the remainder. More of a biological and bacterialogical approach. Basically the fish poop is eaten by the snails, snail poop by the copepods, copepod poop by the etc... finally to bacterial conversion of ammonia to nitrate to nitrite to nitrogen gas.

Is either correct? I think that is determined on what you stock your tank with. I think each method will work effectively depending on the stocking conditions.

Thanks.

[inwall75]

<a href=showthread.php?s=&postid=6474986#post6474986 target=_blank>Originally posted</a> by kbmdale
Silica sand....Its funny when it comes to sand that the hobby veiws silica as BAD...But when it comes to tanks no one seems to care that the glass and seal is made of the same thing...

:lol:

"Reefer tales" seem to be much worse than "old wive's tales".

[kbmdale]

<a href=showthread.php?s=&postid=6475034#post6475034 target=_blank>Originally posted</a> by inwall75
:lol:

"Reefer tales" seem to be much worse than "old wive's tales".


"there once was a sand bed that stayed in a bucket, when the water got foul the old man decided to chuck it""


:lol:

[aubee91]

<a href=showthread.php?s=&postid=6474754#post6474754 target=_blank>Originally posted</a> by inwall75
Bioturbation is basically the mixing/turning over of sediments....what is typically called sand-stirring. It helps move water and it's wastes around. There are some critters who will go to the anaerobic portion of the bed but not many. Basically, the denitrification is NOT occurring in the anaerobic section of your sandbed...it is occurring at the anoxic interface. The more water you can get to this anoxic interface, the more efficient your bed is at denitrification.


Okay, that makes a lot of sense. The nutrients have to get to the bacteria that can convert them.


On a newer bed, this anoxic interface is much deeper than on an older bed. Other critters are quite helpful then. On an older bed, you might be fine with critters that don't go too deep. EDIT: But will it still work without them? Yes.

It this always the case that the interface gets shallower with age? If so, it would seem to imply that Bomber is correct about the bed being a sink. Does an abundance of critters slow the "shallowing" of the interface?

[aubee91]

<a href=showthread.php?s=&postid=6475023#post6475023 target=_blank>Originally posted</a> by Acipenser
I think there are two differing view points on this factor.

In my readings it seems that Calfo believes that in our reef systems our DSBs typically do not support the infaunal populations at levels that are necessary, based on our stocking the tank with creatures that eat the infauna. His use of a DSB in a bucket uses flow and mechanical filtration to prevent the accumulation of detritus in the sediment of the bucket, and uses the normal denitrification process of the bateria to reduce nitrates. More of a combined mechanical and bacterial approach.

Dr. Ron believes that DSB can be constructed to maintain sufficient populations of infauna. In this approach, detritus is processed by the various size creatures to eliminate as much nitrogenous waste as possible before bacterial processing. Then the normal denitrification process of the bateria in the sandbed is used to process the remainder. More of a biological and bacterialogical approach. Basically the fish poop is eaten by the snails, snail poop by the copepods, copepod poop by the etc... finally to bacterial conversion of ammonia to nitrate to nitrite to nitrogen gas.

Is either correct? I think that is determined on what you stock your tank with. I think each method will work effectively depending on the stocking conditions.

Thanks.

Or maybe both are correct and both processes occur to different extents? In the case Anthony supports, the bed is acting mostly as a phosphate sink that will fill up and eventually need to be removed. Thus the putting it in an easily removable bucket. In the case Dr. Ron supports, the nutrients are (mostly) bound up in the bodies of the infauna and little sinking of phosphate occurs in the bacteria and/or bound to the grains of the substrate so the bed can operate indefinitely (or at least a potentially very long time) before failing. As long as the infauna survive.

The only drawbacks I can see to Dr. Ron's view is a) the cost of the kits to supply/resupply the infauna and b) not knowing whether/when this needs to be done. On the plus side, the DSB should at least act as a sink for a while even after an infaunal die off, right? If this is the case, could a bed that has a lot of stored phosphate in it be "rejuvenated" by adding critters? I.e. will they be able to "eat up" the phosphate that is sunk in the bed? Could a bed that is getting cyano growing on it and showing signs of imminent crash or failure be "fixed" just by adding critters?

[kbmdale]

Don't use the B word in this thread.... :lol:

[aubee91]

<a href=showthread.php?s=&postid=6475264#post6475264 target=_blank>Originally posted</a> by kbmdale
Don't use the B word in this thread.... :lol:

Bed? Bucket? Bacteria? :)

[kbmdale]

BOMBER!!!.... I don't trust people who disapear when thier credentials are questioned.

[aubee91]

<a href=showthread.php?s=&postid=6475336#post6475336 target=_blank>Originally posted</a> by kbmdale
BOMBER!!!....

I think we'll be all right if we all discuss folks' ideas based on the merit of those ideas rather than the credentials of those who espouse them. This thread is one of the few on RC in a long time that has been able to discuss these topics without a bunch of insults and closure. Let's try to keep it on track here. ;)

[inwall75]

<a href=showthread.php?s=&postid=6475336#post6475336 target=_blank>Originally posted</a> by kbmdale
BOMBER!!!.... I don't trust people who disapear when thier credentials are questioned.

Kris,

Let's not go there. Bomber is gone by choice and that truly is his right. There's clearly more going on than anyone on this thread knows.

Let's just have the discussion and not have the thread closed.

[kbmdale]

I agree, there has been little arguement in this thread, but for every expert that claims a dsb will turn into a sink, there is one that says it doesn't. I just think the thread would be better off without the logic of the big B for once. His logic has always served one purpose ;).

Now I will say no more on that

[inwall75]

<a href=showthread.php?s=&postid=6475177#post6475177 target=_blank>Originally posted</a> by aubee91
It this always the case that the interface gets shallower with age? If so, it would seem to imply that Bomber is correct about the bed being a sink. Does an abundance of critters slow the "shallowing" of the interface?

Actually, IMO, that's the point of this whole discussion. How do we make our beds more efficient. Improper construction, husbandry, etc. can result in a "failed" DSB pretty quickly. Partially correct construction, husbandry, etc. can result in a "failed" DSB over a longer period of time. How do we MAXIMIZE a DSB seems to be the point of the whole thread.

[inwall75]

<a href=showthread.php?s=&postid=6475023#post6475023 target=_blank>Originally posted</a> by Acipenser
I think there are two differing view points on this factor.

In my readings it seems that Calfo believes that in our reef systems our DSBs typically do not support the infaunal populations at levels that are necessary, based on our stocking the tank with creatures that eat the infauna. His use of a DSB in a bucket uses flow and mechanical filtration to prevent the accumulation of detritus in the sediment of the bucket, and uses the normal denitrification process of the bateria to reduce nitrates. More of a combined mechanical and bacterial approach.

Dr. Ron believes that DSB can be constructed to maintain sufficient populations of infauna. In this approach, detritus is processed by the various size creatures to eliminate as much nitrogenous waste as possible before bacterial processing. Then the normal denitrification process of the bateria in the sandbed is used to process the remainder. More of a biological and bacterialogical approach. Basically the fish poop is eaten by the snails, snail poop by the copepods, copepod poop by the etc... finally to bacterial conversion of ammonia to nitrate to nitrite to nitrogen gas.

Is either correct? I think that is determined on what you stock your tank with. I think each method will work effectively depending on the stocking conditions.

Thanks.

I was busy typing or was on the phone. This is a post worth reading and discussing IMO.

[barryhc]

Yeah buddy!!!!!!!!!

quote:
--------------------------------------------------------------------------------
Originally posted by Acipenser
I think there are two differing view points on this factor.

In my readings it seems that Calfo believes that in our reef systems our DSBs typically do not support the infaunal populations at levels that are necessary, based on our stocking the tank with creatures that eat the infauna. His use of a DSB in a bucket uses flow and mechanical filtration to prevent the accumulation of detritus in the sediment of the bucket, and uses the normal denitrification process of the bateria to reduce nitrates. More of a combined mechanical and bacterial approach.

Dr. Ron believes that DSB can be constructed to maintain sufficient populations of infauna. In this approach, detritus is processed by the various size creatures to eliminate as much nitrogenous waste as possible before bacterial processing. Then the normal denitrification process of the bateria in the sandbed is used to process the remainder. More of a biological and bacterialogical approach. Basically the fish poop is eaten by the snails, snail poop by the copepods, copepod poop by the etc... finally to bacterial conversion of ammonia to nitrate to nitrite to nitrogen gas.

Is either correct? I think that is determined on what you stock your tank with. I think each method will work effectively depending on the stocking conditions.

Thanks.
--------------------------------------------------------------------------------



<a href=showthread.php?s=&postid=6475263#post6475263 target=_blank>Originally posted</a> by aubee91
Or maybe both are correct and both processes occur to different extents? In the case Anthony supports, the bed is acting mostly as a phosphate sink that will fill up and eventually need to be removed. Thus the putting it in an easily removable bucket. In the case Dr. Ron supports, the nutrients are (mostly) bound up in the bodies of the infauna and little sinking of phosphate occurs in the bacteria and/or bound to the grains of the substrate so the bed can operate indefinitely (or at least a potentially very long time) before failing. As long as the infauna survive.

The only drawbacks I can see to Dr. Ron's view is a) the cost of the kits to supply/resupply the infauna and b) not knowing whether/when this needs to be done. On the plus side, the DSB should at least act as a sink for a while even after an infaunal die off, right? If this is the case, could a bed that has a lot of stored phosphate in it be "rejuvenated" by adding critters? I.e. will they be able to "eat up" the phosphate that is sunk in the bed? Could a bed that is getting cyano growing on it and showing signs of imminent crash or failure be "fixed" just by adding critters?

I think were really starting to get somewhere now. We don't seem to quite have the answers here yet, although I basicly agree with both of the posts above.

We sure have zeroed in on one very large question though, and I think that the learning that we get on this issue will have far reaching implications on all reef keeping issues, like RDSB, and refugium, and reactors, and . . . . .

Thanks to everyone for getting us here, and being so nice about it along the way!!!!

Happy Reef Keeping ! > barryhc :) :)

[Amphiprionocellaris]

originally posted by aubee91
Or maybe both are correct and both processes occur to different extents? In the case Anthony supports, the bed is acting mostly as a phosphate sink that will fill up and eventually need to be removed. Thus the putting it in an easily removable bucket. In the case Dr. Ron supports, the nutrients are (mostly) bound up in the bodies of the infauna and little sinking of phosphate occurs in the bacteria and/or bound to the grains of the substrate so the bed can operate indefinitely (or at least a potentially very long time) before failing. As long as the infauna survive.

The only drawbacks I can see to Dr. Ron's view is a) the cost of the kits to supply/resupply the infauna and b) not knowing whether/when this needs to be done. On the plus side, the DSB should at least act as a sink for a while even after an infaunal die off, right? If this is the case, could a bed that has a lot of stored phosphate in it be "rejuvenated" by adding critters? I.e. will they be able to "eat up" the phosphate that is sunk in the bed? Could a bed that is getting cyano growing on it and showing signs of imminent crash or failure be "fixed" just by adding critters?
First, two comments on the bucket method
1) Getting nutrients from the tank to the bucket could be very difficult. However, good turnover and a little engineering should circumvent that aspect.
2) Restarting a sand bed upon removal of the old one could be problematic (going through a new cycle). It is possible (if not likely), though, that the denitrators in the live rock could pick up the slack until the new bed is established. Or, perhaps, one could use a staggered pair of buckets, so that you always have a good bed on the system, even when replacing. Sort of like staggering the lights on a tank so that only half of them are old.

There's also the concern that not all the phosphate will get into the bucket, but the phosphate left should be marginal enough that it doesn't matter. There's also the problem of knowing when the bucket is ready to be switched out.

I'm not trying to knock anyone's method. I'm just pointing out potential problems so that they can be fixed (as per the goal of this thread). A little experimentation should provide the necessary information for both methods (eg. when the bucket is saturated and questions about restoring fauna), and I'm going to be in a position for some heavy research starting next semester:).

[KAiNE]

Question..... wish i had asked this some time ago.

Since getting back into the hobby a few things have changed, sand being one of them. I ran BB from day one (other than a FO with CC and a UGF). In the late 80's to early 90's I never heard of sand beds and the thought of having sand in ones reef tank was unheard of, atleast to me. Now, in 05-06, all this talk about going back to BB...
Why did everyone seem to migrate to sand in the first place? the only reason i see is NO3 was there another reason?

[bertoni]

<a href=showthread.php?s=&postid=6473310#post6473310 target=_blank>Originally posted</a> by Acipenser
Bertoni,



Care to elaborate? PM me if necessary.

Seems to me that they have a lot of information on the subject and to flatly reject their ideas seems a little irresponsible for this thread.

I didn't write the quote you posted.

[Weatherman]

<a href=showthread.php?s=&postid=6475925#post6475925 target=_blank>Originally posted</a> by KAiNE
Why did everyone seem to migrate to sand in the first place? the only reason i see is NO3 was there another reason?

That's all.

And, it looks pretty. :p

[bertoni]

<a href=showthread.php?s=&postid=6473179#post6473179 target=_blank>Originally posted</a> by Sindjin
Thats just it... to me COOKING (dark curing) is even more essential in a DSB than a BB. It kills off all the algaes and allows bacteria from inside the rock to expell all the PO4. The critters you speak off to process waiste is the bacteria. Cooking the rock does NOT kill off this bacteria... nor does it kill all the "life" on the rock. Rocks will shed. The problem is we can't determine how much because we dont know what is actually built up inside it. Thas why to me it is vital for a DSB to have Rock that is a clean as possible.

I think this is all wrong, but I don't want yet another rock cooking thread, so I'm not going to debate. I would request that the rock cooking debate be taken elsewhere. It seems we both agree that it's not specific to DSBs.

[barryhc]

One of the reasons is for the animals that live in the sand, there are a lot of them. Another is aesthetics. Both apply to me.

NNR comes in third for me, but since I'm going to have sand for the first two reasons, I feel the need to do the best I can with the third.

> barryhc :)

[bertoni]

<a href=showthread.php?s=&postid=6474206#post6474206 target=_blank>Originally posted</a> by barryhc
IIs silica that harmful to the animals, and if so, are there alternatives, that are available down to .1 or .2mm?

Silica sand works quite well in practice, and can be better than the aragonite available for purchase. In Dr Shimek's course, the best DSB was silica, as measured by fauna.



I still don't care for the idea of "mud" and "flour-szed" substrate in the display, for reasons of clumping, PO4 release, and poor diffusion charachteristics.


Why do you think any of those are issues? We're not depending on diffusion in our sandbeds at that scale.

[bertoni]

<a href=showthread.php?s=&postid=6474398#post6474398 target=_blank>Originally posted</a> by aubee91
But IIRC, Dr. Ron says that the fauna on live rocks won't
populate the DSB anyway as they are not benthic. If so, seems like the critters on the live rock wouldn't be useful for DSB waste processing anyway.

I don't see any point in killing off interesting creatures for which I've paid good money. If you don't want them, dark-treat (cooking) is perhaps okay.

[Amphiprionocellaris]

<a href=showthread.php?s=&postid=6475925#post6475925 target=_blank>Originally posted</a> by KAiNE
Question..... wish i had asked this some time ago.

Since getting back into the hobby a few things have changed, sand being one of them. I ran BB from day one (other than a FO with CC and a UGF). In the late 80's to early 90's I never heard of sand beds and the thought of having sand in ones reef tank was unheard of, atleast to me. Now, in 05-06, all this talk about going back to BB...
Why did everyone seem to migrate to sand in the first place? the only reason i see is NO3 was there another reason?
There are lots of reasons. From what I've read, the sand beds pioneered by the likes of Jaubert were radical improvements in the husbandry of reefs. Primarily, they were more natural (and higher in biodiversity), and seemed to be less maintenance than their bare-bottom counterparts (I say "seemed" because I don't have first-hand experience with both). Then, as more people did DSB, and more couldn't get it to work (for various reasons), some gave up and went to bare-bottom (it was, after all, the first method to work). It is also worth noting, however, that both bare-bottom and sand bed methods have changed a lot since their first inception (as this thread suggests).

Of course, by the time I finish this post, someone else will have answered, but that's my look at it.

[bertoni]

<a href=showthread.php?s=&postid=6474678#post6474678 target=_blank>Originally posted</a> by aubee91
Okay, I'm unfamiliar with the difference between bioturbation and just frequent stirring. This bioturbation only occurs in the aerobic portion of the bed, right? So what is it about the bioturbation that increases the efficiency compared to frequent stirring by larger critters? Is it simply because there are so many of the smaller critters and they just turn the grains over more frequently on average?

Bioturbation is done by organisms. Ants and earthworms are great terrestrial examples. The process moves water and nutrients in and out of the sandbed. I don't know what you mean by "stirring", exactly, so I can't comment more.

Diffusion is worthless to move nutrients in and out of the sandbed because it's far too slow. Sandbeds do get some bulk flow that should help some, but without animals, the sandbed isn't going to function the same way. No processing of solid wastes as desired, etc.

[KAiNE]

<a href=showthread.php?s=&postid=6476033#post6476033 target=_blank>Originally posted</a> by barryhc
One of the reasons is for the animals that live in the sand, there are a lot of them. Another is aesthetics. Both apply to me.

NNR comes in third for me, but since I'm going to have sand for the first two reasons, I feel the need to do the best I can with the third.

> barryhc :)

I see....

So what has changed in BB that eliminated the issues we used to have? Dont say skimmers because we had em then, good ones too. The solution back in BC/BB was to starve the fish or have no fish at all. Now in AD/BB what is the solution to NO3, other than siphoning the bottom and WC (same as any method)?

As far as the aesthetics, i agree but i think a SSB looks better than a DSB but thats an opinion.

[bertoni]

<a href=showthread.php?s=&postid=6475177#post6475177 target=_blank>Originally posted</a> by aubee91
[B If so, it would seem to imply that Bomber is correct about the bed being a sink. Does an abundance of critters slow the "shallowing" of the interface? [/B]

There's no evidence or studies behind statements that a sandbed must turn into a sink, and there are counterexamples of beds that have lived a long time, by aquarium standards.

[barryhc]

<a href=showthread.php?s=&postid=6476063#post6476063 target=_blank>Originally posted</a> by bertoni
Silica sand works quite well in practice, and can be better than the aragonite available for purchase. In Dr Shimek's course, the best DSB was silica, as measured by fauna.

I'm glad to hear that.

Why do you think any of those are issues? We're not depending on diffusion in our sandbeds at that scale. [/B][/QUOTE]

We aren't?

At what scale?

If not then what is moving the nutrients and compounds, and what is the necessary function of the mud?

If the mud is not included, will it cause the sand bed to function improperly?

Some of the things I need to learn. > barryhc :)

[Weatherman]

<a href=showthread.php?s=&postid=6476105#post6476105 target=_blank>Originally posted</a> by KAiNE
I see....

So what has changed in BB that eliminated the issues we used to have? Dont say skimmers because we had em then, good ones too. The solution back in BC/BB was to starve the fish or have no fish at all. Now in AD/BB what is the solution to NO3, other than siphoning the bottom and WC (same as any method)?

As far as the aesthetics, i agree but i think a SSB looks better than a DSB but thats an opinion.

Loose rock structure and vigorous flow to keep organic particulates in suspension, and running skimmers real wet to get the particulates out as fast as possible.

It seems to work. A majority of BB people, in a recent poll, had no significant nitrates.

[Amphiprionocellaris]

<a href=showthread.php?s=&postid=6476105#post6476105 target=_blank>Originally posted</a> by KAiNE
So what has changed in BB that eliminated the issues we used to have? Dont say skimmers because we had em then, good ones too. The solution back in BC/BB was to starve the fish or have no fish at all. Now in AD/BB what is the solution to NO3, other than siphoning the bottom and WC (same as any method)?

I'm not quite sure on this, but my understanding is that the "new" BB method is to use extreme water flow to keep everything in suspension so that it can be removed (by skimmer, water change, etc.) before breaking down. That's just my understanding. Back on subject (sorta), it is worth saying again that the same principle (high water flow to prevent accumulation) can be used in all tanks, regardless of substrate.

[bertoni]

In practice, diffusion occurs and is needed, but I just can't understand how very fine, "flour"-like sediments could be a problem if used as a <b>part</b> of the mix. Perhaps I should have been more clear. I don't propose using only flour-level substrate, just as a part of the mix to get back to the ideal particle balance. The other Carib Sea products are all too coarse on their own.

[Amphiprionocellaris]

<a href=showthread.php?s=&postid=6476136#post6476136 target=_blank>Originally posted</a> by Weatherman
A majority of BB people, in a recent poll, had no significant nitrates.
Of course, as far as nitrates go, good LR should/will act as a denitrification zone. I believe there was an article in either Reefkeeping or Advanced Aquarist that detailed denitrification in LR.

[alten78]

its been an interesting thread to read to say the least. Alot of good opinions and theories on how things work and dont work, all while staying for the most part on track :thumbsup:

What I was waiting to read through all this was the actual day to day, weekly, or monthly maintenance and husbandry by those who havent had "problems" and those that have. The only thing I saw (unless I missed it) was not to stir it up or vacuum?

I kept a ssb (mainly for aesthetics and did not rely on critters) by blowing off and stiring on a weekly basis and have never seen cyano or hair algae in the tank *knocks on wood.* I will be moving to a 75 here in the next month or so and would really be interested in the actual procedures others have used as I am leaning towards dsb.

Thanks all!

~ba

[Weatherman]

<a href=showthread.php?s=&postid=6476185#post6476185 target=_blank>Originally posted</a> by Amphiprionocellaris
Of course, as far as nitrates go, good LR should/will act as a denitrification zone. I believe there was an article in either Reefkeeping or Advanced Aquarist that detailed denitrification in LR.

Very true.

And that’s why the old-style Berlin tanks relied on a huge amount of live rock. The focus, then, was to perform denitrification in the tank. Didn’t always work very well.

The approach now is to get as much of that stuff out as possible before it breaks down.

[KAiNE]

<a Originally posted</a> by Weatherman
Loose rock structure and vigorous flow to keep organic particulates in suspension, and running skimmers real wet to get the particulates out as fast as possible.

It seems to work. A majority of BB people, in a recent poll, had no significant nitrates.

Other than the flow, this isn't new to me. I can see how higher flow will keep organics in suspension thereby allowing the skimmer to get it.
I am running a SSB (1" average, bare in the back). I also ran PVC under all my rock pushed via a Iwaki40RLT to prevent buildup in the low flow areas and to provide "pod" rich water to these areas. I also skim slightly wet and get roughly 1 gallon a day. I can definatly see how a DSB could go south for the reasons described in this thread but with either method or any combination there of, it boils down to import vs. export. If you're not exporting heavily, you will have problems no matter what method you use.

[barryhc]

<a href=showthread.php?s=&postid=6476136#post6476136 target=_blank>Originally posted</a> by Weatherman
Loose rock structure and vigorous flow to keep organic particulates in suspension, and running skimmers real wet to get the particulates out as fast as possible.

I think this is right, and these are huge pluses in almost any kind of system.

> barryhc :)

[barryhc]

<a href=showthread.php?s=&postid=6476171#post6476171 target=_blank>Originally posted</a> by bertoni
In practice, diffusion occurs and is needed, but I just can't understand how very fine, "flour"-like sediments could be a problem if used as a <b>part</b> of the mix. Perhaps I should have been more clear. I don't propose using only flour-level substrate, just as a part of the mix to get back to the ideal particle balance. The other Carib Sea products are all too coarse on their own.

Carib sea has Araganite at .1 to 1mm, and .1mm is within the range of "mud". Is there a reason why we "need" finer substrates than this in the tank?

Thanks > barryhc :)

[SDguy]

<a href=showthread.php?s=&postid=6476096#post6476096 target=_blank>Originally posted</a> by bertoni
Sandbeds do get some bulk flow that should help some, but without animals, the sandbed isn't going to function the same way. No processing of solid wastes as desired, etc.

Isn't this contrary to the idea of keeping flow high and particle size small to prevent actual particulates from entering the bed itself?

[joefish]

<a href=showthread.php?s=&postid=6473880#post6473880 target=_blank>Originally posted</a> by Amphiprionocellaris
I only partially agree. I wasn't talking about a tank-consuming bloom of algae; that is indeed a sign of a problem. I was talking about little blooms of algae; say, a little hair algae in a corner of the tank. It's a sign of phosphate, but the phosphate is locked up in the algae, rather than being in the water column where it can do harm (one principle of a refugium). Perhaps that phosphate came from waste that didn't make it into an area where it could be processed. All I'm saying is that algae (small blooms that affect aesthetics, not the big ones that kill stuff) shouldn't automatically be considered a sign of a bad DSB. Algae can be, and often is, a product of a bad sand bed, but not all algae comes from having a bad bed.


A sign of any algae should be treated as nutrients are building up . This doesn't mean a failed sand bed , it can mean many things . With a BB tank a bloom means you missed something and husbandry can make up for it . With a DSB , when do you know it's a bloom from cycling fauna or your husbandry skills need to be upgraded ?

When I use the term failed DSB , it means I kept upgrading my husbandry skills with no avail .

It's a sign of phosphate, but the phosphate is locked up in the algae, rather than being in the water column where it can do harm (one principle of a refugium). Perhaps that phosphate came from waste that didn't make it into an area where it could be processed.

Your not far off , but not right either . There will be some PO4 consumed and locked up by algae ( this is true) , but unless you find where the PO4 is starting , it will keep feeding the
free floating PO4 into the water .

Again if stony corals are being kept , the sight of most algaes should be used as a sign to correct something .



I also don't like the use of refugiums , but that's another thread .:p




PS; Reefers who have DSB working correctly , when you see algae starting to form , how do you know when it's just a fauna cycle or a sign of a bigger problem ?

[barryhc]

<a href=showthread.php?s=&postid=6476199#post6476199 target=_blank>Originally posted</a> by alten78
its been an interesting thread to read to say the least. Alot of good opinions and theories on how things work and dont work, all while staying for the most part on track :thumbsup:

Isn't it great !! :thumbsup: :thumbsup:

What I was waiting to read through all this was the actual day to day, weekly, or monthly maintenance and husbandry by those who havent had "problems" and those that have. The only thing I saw (unless I missed it) was not to stir it up or vacuum? :thumbsup: :thumbsup:

You missed it partly. The general consensus is that up to 2" is certainly shallow, and stirring and vacuuming all the time is common practice. All the time? As much as you want. It is generally accepted that shallow sand is likely to be a Nitrate producer, but it can be handled.

> barryhc :)

[onthefly]

Originally posted by inwall75
You have to make a pretty big mistake to make aragonite turn into a brick.

Well plenty of people have done it....and in my case, no "big mistakes" were made. My only guess was the lack of sand movement and high flow (75x). Since the only section that was solid was the section in the highest flow. I had plenty critters, but lacked nassaraius snails or some other type of sand "mover".

For those interested in silica based sands......the major contaminating compound is feldspar (like weatherman posted). Get an MSDS on the composition of the sand and make sure it isn't there. I've built 2 silica based tanks with "quikrete medium grade commercial sand" from Lowes ($6 for 100lbs). Ivory white, southdown size grains, and the MSDS says 99.9% silica sand.

[Acipenser]

Bertoni,

I am sorry. I creditted the quote to the wrong individual. I should have written barryhc.

quote:
--------------------------------------------------------------------------------
Originally posted by Acipenser
Bertoni,

Care to elaborate? PM me if necessary.

Seems to me that they have a lot of information on the subject and to flatly reject their ideas seems a little irresponsible for this thread.
--------------------------------------------------------------------------------

Sorry for the confusion.


__________________

[joefish]

As much as I like Anthony , I don't agree with the DSB bucket thought .

Now if I'm getting this right , a DSB only process what falls on it . This being it's not used like a mechanical filter and water doesn't actualy pass through it .

So why would you use a bucket to collect detritus and process it instead of just mechanicaly filtering it or siphoning it out ?

This has bugged me since the first time I've heard it . Since Po4 is realeased during the N cycle it's almost counter productive .

[kbmdale]

<a href=showthread.php?s=&postid=6476586#post6476586 target=_blank>Originally posted</a> by joefish
As much as I like Anthony , I don't agree with the DSB bucket thought .

Now if I'm getting this right , a DSB only process what falls on it .

I don't think that is right, the problem is it doesn't process the large stuff that falls on it. Its a biological filter not a mechanical one. The fauna and microfauna consume some of what falls on it but not in a grand enough scale to be effective..

[barryhc]

<a href=showthread.php?s=&postid=6476490#post6476490 target=_blank>Originally posted</a> by onthefly
Well plenty of people have done it....and in my case, no "big mistakes" were made. My only guess was the lack of sand movement and high flow (75x). Since the only section that was solid was the section in the highest flow. I had plenty critters, but lacked nassaraius snails or some other type of sand "mover".

This sounds a bit strange ( the high flow ), but what particle size were you using? Those sand movers are a BIG plus. Maybe the critters you had didn't like the flow, and stayed in lower flow areas. Nassarius snails are excellent "movers" along with cucumbers.

For those interested in silica based sands......the major contaminating compound is feldspar (like weatherman posted). Get an MSDS on the composition of the sand and make sure it isn't there. I've built 2 silica based tanks with "quikrete medium grade commercial sand" from Lowes ($6 for 100lbs). Ivory white, southdown size grains, and the MSDS says 99.9% silica sand.

What are "southdown grain sizes", and was this the material that got hard? Istill don't like the "mud" stuff, and I'm going to keep it out of my tank until its use is justified.

> barryhc :)

[npaden]

<a href=showthread.php?s=&postid=6476199#post6476199 target=_blank>Originally posted</a> by alten78
What I was waiting to read through all this was the actual day to day, weekly, or monthly maintenance and husbandry by those who havent had "problems" and those that have. The only thing I saw (unless I missed it) was not to stir it up or vacuum?


I think something that has been mentioned by a few of us is that there isn't a magical bullet. The amount of stuff you take out of your tank needs to equal or exceed what you put into your tank. It doesn't matter if it is a BB, SSB or DSB. I've seen people do this through siphoning detritus, vaccumming shallow sandbeds, macro algae refugiums, even through a xenia refugium. And another thing that I think is important regardless of your substrate choice is excellent water flow and a very good skimmer.

One thing that I think I've noticed from this thread is that it is VERY difficult to point out even 1 or 2 items that are going to make the difference between a successful DSB tank vs. an unsuccessful one. I don't really see anything that joefish did to cause his to fail but it seems that once he switched to BB he didn't have any additional nutrient problems. I'm by no means a perfectionist who did everything right but my tank seems to be running like a champ 4 1/2 years. I don't have an explanation for that.

FWIW, Nathan

[joefish]

<a href=showthread.php?s=&postid=6476635#post6476635 target=_blank>Originally posted</a> by kbmdale
I don't think that is right, the problem is it doesn't process the large stuff that falls on it. Its a biological filter not a mechanical one. The fauna and microfauna consume some of what falls on it but not in a grand enough scale to be effective..

Yes , but water doesn't flow through the sand . So how does it lower NO3 then?

[Weatherman]

<a href=showthread.php?s=&postid=6476586#post6476586 target=_blank>Originally posted</a> by joefish
As much as I like Anthony , I don't agree with the DSB bucket thought .

Now if I'm getting this right , a DSB only process what falls on it . This being it's not used like a mechanical filter and water doesn't actualy pass through it .

So why would you use a bucket to collect detritus and process it instead of just mechanicaly filtering it or siphoning it out ?

This has bugged me since the first time I've heard it . Since Po4 is realeased during the N cycle it's almost counter productive .


I think the theory is that the DSB in a bucket will process any nitrate that has entered the water through diffusion.

But, as you mention, the problem with the theory is that nitrate is simply an electron receptor for the decomposition of organic matter (which may contain phosphate). The organic matter has to get into the sand bed also, and once there, there is no phosphate export mechanism.

[Acipenser]

I think we need to clear up a few things. People are using a few words incorrectly which may be leading to some confusion.

nitrification- the reduction of ammonia to nitrate by nitrosomonas and nitrobacter bacteria. (requires oxygen)

denitrification - the removal of nitrogen compounds by the conversion of nitrate to nitrogen gas. (does not require oxygen)

Also there seems to be a little confusion on the use of the words nutrients. Strictly speaking they are not being used incorrectly, but I think we could clear things up by using more desciptive terms. People are using nutrients to refer to particulate matter (poop, detritus, etc..) and to dissolved organic compounds (DOC)(ammonia, nitrite, nitrate, etc..). We need to have a clear understanding of what is referred to. This different compounds are taken care of in different ways.

For instance:

First, two comments on the bucket method
1) Getting nutrients from the tank to the bucket could be very difficult. However, good turnover and a little engineering should circumvent that aspect.

The nutrients that Calfo was referring to are Nitrates. They will be carried to the bucket through the water supply. Particulate matter is supposed to pass through the bucket or collect prior to entry by mechanicla filtration and not to be processed in the bucket.

Diffusion is worthless to move nutrients in and out of the sandbed because it's far too slow.

Here Bertoni is referring to dissolved organic compounds which will diffuse from an area of high concentration to an area of low concentration, no matter what we do.

We need to have a clear understanding of what others are referring to in order to make a good discussion.

[kbmdale]

<a href=showthread.php?s=&postid=6476709#post6476709 target=_blank>Originally posted</a> by joefish
Yes , but water doesn't flow through the sand . So how does it lower NO3 then?


ACTUALLY IT DOES... The part I think your not getting is the biological attraction between 2 chemical compounds or the splitting there of... The sand bed particles attract water column particles.

LOL..thats lamons terms..heck I'm not a PHD..Bertoni could explain it better.

[inwall75]

Onthefly,

I'm sorry that my "onthefly" comment was not thoroughly thought through. I've not had a problem but there are numerous reasons why that could be.

Joefish,

Even if waste doesn't fall on the DSB, it will rot and will produce ammonia. Then you don't have control over it. If the ammonia is in the water from waste that rotted elsewhere, the bacteria still want to engage in ETS. This ammonia will go through the water column and proximity really isn't an issue to them.

[tsquad]

<a href=showthread.php?s=&postid=6476490#post6476490 target=_blank>Originally posted</a> by onthefly
Well plenty of people have done it....and in my case, no "big mistakes" were made. My only guess was the lack of sand movement and high flow (75x). Since the only section that was solid was the section in the highest flow. I had plenty critters, but lacked nassaraius snails or some other type of sand "mover".

For those interested in silica based sands......the major contaminating compound is feldspar (like weatherman posted). Get an MSDS on the composition of the sand and make sure it isn't there. I've built 2 silica based tanks with "quikrete medium grade commercial sand" from Lowes ($6 for 100lbs). Ivory white, southdown size grains, and the MSDS says 99.9% silica sand.

An aragonite sand bed (CaCO3) will turn into a brick for one (or both) of these two reasons:

1. You have pH swings. Lower pH (at night/morning) will dissolve some of the CaCO3, and then later that day/evening, when the pH has risen again, the sand that dissolved will solidify again. Over time, the entire bed will just become a rock. Similar to a snowbank...first you have snow. It melts, then refreezes that night. After a week or so, you have a solid block of ice.

2. Your grain sizes are irregular. Jagged and crystalline (a lot of SiO2 sands are like this, partly causing the myth of silica sand being bad; it's obviously not due to it's chemical composition, as the sand is the exact same thing as the glass, just the glass is amorphous) grains have a tendency to compact, causing the bed to solidify.

[barryhc]

<a href=showthread.php?s=&postid=6476456#post6476456 target=_blank>Originally posted</a> by joefish
When I use the term failed DSB , it means I kept upgrading my husbandry skills with no avail .

If your husbandry skills were being upgraded significantly enough to mention it here, then maybe it was too late, or not enough algae eaters, or not enough sand "stirrers", or . . . .

Again if stony corals are being kept , the sight of most algaes should be used as a sign to correct something .

Like critter populations, or "mud" in your filter.

Reef tanks are not defined as SPS dominated. Many SPS are touchy about nutrients, and many are not as much so. Many long term DSB tanks have healthy populations of all types of SPS.

> barryhc :)

[inwall75]

Good Heavens....I wish the phone would stop ringing.

After reading what I missed because of the phone call and my typing, I realized that I needed to point out that ETS is Electron Transport System.

[joefish]

<a href=showthread.php?s=&postid=6476744#post6476744 target=_blank>Originally posted</a> by Weatherman
I think the theory is that the DSB in a bucket will process any nitrate that has entered the water through diffusion.

But, as you mention, the problem with the theory is that nitrate is simply an electron receptor for the decomposition of organic matter (which may contain phosphate). The organic matter has to get into the sand bed also, and once there, there is no phosphate export mechanism.

Now I'm totaly impressed with you . You can take my jiberish and make it sound smart .:lol:

[barryhc]

<a href=showthread.php?s=&postid=6476096#post6476096 target=_blank>Originally posted</a> by bertoni
Diffusion is worthless to move nutrients in and out of the sandbed because it's far too slow. Sandbeds do get some bulk flow that should help some, but without animals, the sandbed isn't going to function the same way. No processing of solid wastes as desired, etc.

"Worthless" is a HUGE word.

Sand beds get a lot more Advection ( bulk ) floe when they have a layer of .5 to 1.5mm sand at the top, and with the much larger flow that this allows.

I sure do like the animals, I'm going to keep them in my tank.

> barryhc :)

[inwall75]

<a href=showthread.php?s=&postid=6476824#post6476824 target=_blank>Originally posted</a> by barryhc
Sand beds get a lot more Advection ( bulk ) floe when they have a layer of .5 to 1.5mm sand at the top, and with the much larger flow that this allows.


That's been my experience as well.

[joefish]

<a href=showthread.php?s=&postid=6476755#post6476755 target=_blank>Originally posted</a> by kbmdale
ACTUALLY IT DOES... The part I think your not getting is the biological attraction between 2 chemical compounds or the splitting there of... The sand bed particles attract water column particles.

LOL..thats lamons terms..heck I'm not a PHD..Bertoni could explain it better.

Are you saying the DSB in a bucket acts like a magnet and sucks NO3 out of the water ?

If not I'm lost .:p

[joefish]

<a href=showthread.php?s=&postid=6476763#post6476763 target=_blank>Originally posted</a> by inwall75


, the bacteria still want to engage in ETS. This ammonia will go through the water column and proximity really isn't an issue to them.

This is where you lost me .

The DSB is just a breading ground for bacteria that is free floating .

Or is it bacteria sits on the surface and grabs the flowby no3 out of the water ?

[inwall75]

There are bacteria that are motile and run around in the water column. However, they are the rarity compared to most bacteria that are living in biofilms everywhere else.

If water is passing by a bacterium that contains ammonia or Nitrite, then they want to process whatever hits them. Not all of these bacteria are in a sandbed. Some are in LR and some are on the walls of your aquarium, etc. Electron exchange happens pretty quickly and is actually not done on purpose...it's strictly chemical.

EDIT: Here's a great read. http://www.sp.uconn.edu/~terry/Common/respiration.html

[Acipenser]

I think we all need to get a better handle on the process of diffusion.

Definition: Movement of a fluid from an area of higher concentration to an area of lower concentration. Diffusion is a result of the kinetic properties of particles of matter. The particles will mix until they are evenly distributed.

Any dissolved compound will be evenly distributed throughout the water column. When you reduce nitrates in one area (DSB), nitrate will "flow" to that area to equalize the concentration. A sand bed is no obstacle to diffusion. A semi-permeable membrane - yes, sand - no.

The point is that the organic matter does not have to get into the bed to be processed. The organic matter can be broken down anywhere by any creature. It will be converted to ammonia. Ammonia can be processed anywhere two species of bacteria can colonize (glass, pipes, live rock, sand, etc...) and oxygen is present (alkalinity must be present too, but that is another story). The nitrate will get to the lower areas of the DSB (bucket or in tank) no matter what!

I also feel that diffusion is sufficiently fast to work for denitrification in a DSB.

[bertoni]

<a href=showthread.php?s=&postid=6476327#post6476327 target=_blank>Originally posted</a> by barryhc
Carib sea has Araganite at .1 to 1mm, and .1mm is within the range of "mud". Is there a reason why we "need" finer substrates than this in the tank?

Thanks > barryhc :)

Which product goes down to 0.1? That's pretty close. I haven't seen one that fine.

[barryhc]

<a href=showthread.php?s=&postid=6476750#post6476750 target=_blank>Originally posted</a> by Acipenser
I think we need to clear up a few things. People are using a few words incorrectly which may be leading to some confusion.

nitrification- the reduction of ammonia to nitrate by nitrosomonas and nitrobacter bacteria. (requires oxygen)

denitrification - the removal of nitrogen compounds by the conversion of nitrate to nitrogen gas. (does not require oxygen)

Well this is the classic understanding, but it is not very accurate.

Faculative Non-obligate anaerobic bacteria BEGIN the denitrification process in the "hypoxic" ( low oxygen ) zone of the sand bed, which is very thin, and easily disturbed, by vacuuming, siphoning, stirring, etc..

Please avoid the term Anoxic as it was introduced by Bob Goemans, for describing low oxygen, as it is incorrect, and causes a tremendous amount of confusion and controversy.

The dentrification process is COMPLETED in the Anoxic ( devoid of oxygen ) zone of the sand bed, or elsewhere. It is this area of the sand bed where nitrogen gas, and Hydrogen Sulfide, and heavy metals accumulation, either do, or do not, occur.

With a couple of definitions, now in order, . . . .

> barryhc :)

[bertoni]

<a href=showthread.php?s=&postid=6476399#post6476399 target=_blank>Originally posted</a> by SDguy
Isn't this contrary to the idea of keeping flow high and particle size small to prevent actual particulates from entering the bed itself?

I don't follow. I'm talking about movement of water within the sandbed, not on top of it.

[joefish]

<a href=showthread.php?s=&postid=6476776#post6476776 target=_blank>Originally posted</a> by barryhc
If your husbandry skills were being upgraded significantly enough to mention it here, then maybe it was too late, or not enough algae eaters, or not enough sand "stirrers", or . . . .
I treid to folow all the DSB rules with critters.I bought charging kits , fire wormsspighetti worms , cucumbers lots of snails.I think upgrading signifcantly is an overstatemnet . I was uo to 15-20% weekly water changes , using phosban feeding so much less . The when I did the change over I was able to cut back the water changes and feed three time the amount . which I don't think feeding 6 fish should be considered a heavy Bio-load .





Like critter populations, or "mud" in your filter.

Reef tanks are not defined as SPS dominated. Many SPS are touchy about nutrients, and many are not as much so.

I was talking stonies not just SPS's , although some LPS are more forgiving ..

Many long term DSB tanks have healthy populations of all types of SPS.
true , that I thought was the whole purpose of the thread . But algae will still be a sign of to much nutirents ..

> barryhc :) .

[bertoni]

<a href=showthread.php?s=&postid=6476771#post6476771 target=_blank>Originally posted</a> by tsquad
An aragonite sand bed (CaCO3) will turn into a brick for one (or both) of these two reasons:
2. Your grain sizes are irregular.

This part I don't understand. Can you elaborate? I don't see how grain irregularities matter, per se.

[inwall75]

<a href=showthread.php?s=&postid=6476985#post6476985 target=_blank>Originally posted</a> by Acipenser
I think we all need to get a better handle on the process of diffusion.

Definition: Movement of a fluid from an area of higher concentration to an area of lower concentration. Diffusion is a result of the kinetic properties of particles of matter. The particles will mix until they are evenly distributed.

Any dissolved compound will be evenly distributed throughout the water column. When you reduce nitrates in one area (DSB), nitrate will "flow" to that area to equalize the concentration. A sand bed is no obstacle to diffusion. A semi-permeable membrane - yes, sand - no.

The point is that the organic matter does not have to get into the bed to be processed. The organic matter can be broken down anywhere by any creature. It will be converted to ammonia. Ammonia can be processed anywhere two species of bacteria can colonize (glass, pipes, live rock, sand, etc...) and oxygen is present (alkalinity must be present too, but that is another story). The nitrate will get to the lower areas of the DSB (bucket or in tank) no matter what!

I also feel that diffusion is sufficiently fast to work for denitrification in a DSB.

I would say that nitrification can occur quickly...denitrification is a little slower. However, what a great post.

[barryhc]

<a href=showthread.php?s=&postid=6476986#post6476986 target=_blank>Originally posted</a> by bertoni
Which product goes down to 0.1? That's pretty close. I haven't seen one that fine.

Aragamax Sugar Sized Sand > .1 to 1.0mm

Aragamax Select > .5 to 1.5mm

http://www.carib-sea.com/pages/products/marine/substrate/aragonite.html

I would put at least an inch ( maybe two ) of the "Select" on top for "sandstorm resistance", and then however much of the Sugar Size below for denitrification. Probably at least 3-4 inches for me.

> barryhc :)

[Weatherman]

<a href=showthread.php?s=&postid=6476985#post6476985 target=_blank>Originally posted</a> by Acipenser
The point is that the organic matter does not have to get into the bed to be processed. The organic matter can be broken down anywhere by any creature. It will be converted to ammonia. Ammonia can be processed anywhere two species of bacteria can colonize (glass, pipes, live rock, sand, etc...) and oxygen is present (alkalinity must be present too, but that is another story). The nitrate will get to the lower areas of the DSB (bucket or in tank) no matter what!

However, at least dissolved organic matter has to get into the sand bed in order for denitrification to take place.

For bacteria, nitrate is simply an electron receptor, like oxygen, iron, manganese and sulfate. We need to be careful not to consider nitrate to be a "nutrient", or we would have to consider oxygen to be a "nutrient", also.

[joefish]

<a href=showthread.php?s=&postid=6476985#post6476985 target=_blank>Originally posted</a> by Acipenser
I think we all need to get a better handle on the process of diffusion.

Definition: Movement of a fluid from an area of higher concentration to an area of lower concentration. Diffusion is a result of the kinetic properties of particles of matter. The particles will mix until they are evenly distributed.

Any dissolved compound will be evenly distributed throughout the water column. When you reduce nitrates in one area (DSB), nitrate will "flow" to that area to equalize the concentration. A sand bed is no obstacle to diffusion. A semi-permeable membrane - yes, sand - no.

The point is that the organic matter does not have to get into the bed to be processed. The organic matter can be broken down anywhere by any creature. It will be converted to ammonia. Ammonia can be processed anywhere two species of bacteria can colonize (glass, pipes, live rock, sand, etc...) and oxygen is present (alkalinity must be present too, but that is another story). The nitrate will get to the lower areas of the DSB (bucket or in tank) no matter what!

I also feel that diffusion is sufficiently fast to work for denitrification in a DSB.

I agree with Inwall , great post .

I understood most of it , I'm still missing how the no3 gets to and through the low oxgen area of sand fast enough to make a difference in the overall tank water .

[tsquad]

<a href=showthread.php?s=&postid=6477026#post6477026 target=_blank>Originally posted</a> by bertoni
This part I don't understand. Can you elaborate? I don't see how grain irregularities matter, per se.

Well, not necessarily grain irregularities pertaining to size, but shape. Jagged, nonspherical sand grains will definitely be more probable to compact and lock together than spherical grains. You want different sized grains, but not different shapes, that's my understanding.