remote DSB?

[yeame]

is it better to run a 40g tank with water flowing over the sand or should I use a 6g bucket with a reverse flow so the water going up threw the sand and flowing over the top into the sump any info would be great

[outy]

use the 40g idea the other wont work.

[Cody Ray]

<a href=showthread.php?s=&postid=7822584#post7822584 target=_blank>Originally posted</a> by outy
use the 40g idea the other wont work.

You haven't given any proof of your response

[ataylo13]

Check out:

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

[Cody Ray]

(solids) prefiltered water across the DSB is a good idea... but dripping most any kind of water through the bucket is bad. Or at least... it will largely defeat the purpose of having a DSB- denitrification - by bullrushing the media/substrate with oxygen rich water.

This exact process has been done, it is featured in the 2006 issue of Marine fish & reef USA. Water is both pumped in from the top and bottom of the sandbed, it is called an upside-down sandbed. Water that is pumped in from the bottom travels up through the sandbed to the surface. It prevents the sandbed from becoming a nutrient sink. The author of the article demonstrated this by injecting red food dye in a regular DSB and an Upside-down sandbed. Dye that was injected into the DSB took days to resurface from the sandbed, some of it never exited. The dye injected into the UDS would resurface within an hour or less because of the flow. Although the amount of denitrifying bacteria may be reduced by the flow the remaining bacteria recieve a constant flow of water.

[daytonians]

Basically your talking about a fluidized sand bed. The sand is kept partially suspended by the water moving up through it. They can work very well, but they have a big down side. It the water stops flowing for any reason, power goes out, pump breaks, etc., the bed colapses on itself suffocating the bacteria in it, and turning to muck in less than an hour.

[Cody Ray]

It is by no means fluidized, the flow running through the sand isn't very fast.

[BeanAnimal]

So lets get this straight, you asked a question, were given an answer, but already knew what you wanted to hear?

A DSB and an "UPSIDE DOWN" sandbed are two totaly different things. If you do just a little resarch you will find out that pumping water into the bottom of a DSB will result in it NOT BEING A DSB!

So if you want a remote DSB, then you need to have water move over the sand and allow the bottom layers of sand to become anerobic. If you DONT WANT A DSB then feel free to pump water into the bottom of the bed.

You may also want to read the DSB IN A BUCKET thread. You will find out that the using the bucket is likely better than using the remote 40 gallon.

Bean

[Cody Ray]

I have already read that thread.

Unfortunatly I misquoted how the upside-down sandbed works. It uses a plenum and water is still pumped into it however it exits the other side upward onto the top of the bed. It doubles the amount of surface area for the bed. It still has flow through the sand but not as much as I said.

http://i65.photobucket.com/albums/h217/chinchek787/UDS.jpg

sorry for the small image

[daytonians]

Personally, I would be afraid of it building up toxins and releasing them just like under gravel filters are known to do, but that is just me.

[Cody Ray]

<a href=showthread.php?s=&postid=7851194#post7851194 target=_blank>Originally posted</a> by daytonians
Personally, I would be afraid of it building up toxins and releasing them just like under gravel filters are known to do, but that is just me.

By toxins I assume you are refering to nitrate and phosphate. Phosphate is the only one that will bind to sand and once it is bound it won't unbind under normal circumstances (I believe a large downward swing in salinity will cause this). Eventually the sand will no longer be able to bind phosphate and people will experience an algae bloom (system crash). A phosphate reactor could be used to help with this.

Nitrate does not build up in the sand. If I were to guess why people with DSB had crashes I would say that the sand was no longer able to bind phosphate, phosphate built up and caused both algae growth and livestock to die, the dying livestock created a spike in nitrate and when the water was tested high nitrate levels were found and the crash was blamed on nitrate.

[BeanAnimal]

Chin...

I think that the question is going to come down to a high level conversation about the differences between a DSB, a PLENUM and a pseudo DSB that flows oxygenated water throught it.

I am not sure if the discussion will answer the OPs question, as each does something a little different and "best" or "better" can be very subjective.

For a remote DSB likely the bucket aproach will be the easiest and provide suitable results with little trouble and/or maintenance. The shelter from light will reduce a lot of the problems and negate the need for the range of fauna and larger lifeforms that would be needed in a lighted DSB or one that is NOT REMOTE and gets a LOT more detritus settling in it.

The question of critters stirring the "upside down bed" would be something for another topic. I guess "best" would also have to defined with regards to goals before we could compare any type of substrate system and clasify one as better than the other.

Bean

[Cody Ray]

If you read carefully I am not the starter of the thread, I havn't asked a question, Yeame started the thread. There is no need to be rude when responding, so far I have been nothing but polite to you.

[BeanAnimal]

My intent was not to be rude. And I did mistake you for the original poster... if I can edit the post I will...


EDITED

[Cody Ray]

No problem, I enjoy debating issues with others as long as it remains polite if not a little heated ;)

[outy]

[chinchek787, You haven't given any proof of your response.]

no need for proof,,, its common knowledge that a remote dsb works and quite well at that.

the other idea is a problem waiting to happen if not it will still be a nitrate factory at best. why waist sand if you want to do that just play with a coil denitrator. The last i checked those are fine for FO but not quite effecient for a reef.

your talking about a set up that has to be tuned like a race car carburator with a tank failure if flow is to high or low and no real way to know unless you like to constantly test input and output water

[Cody Ray]

I was not refering to proof that the remote DSB would work but that the other wouldn't work. After rereading the article I realized that it wasn't setup like I had stated. Water isn't being forced through the sand however it does have a tendency to travel upward through it because of the way it is setup. This still provides more flow than a regular DSB would but not so much that it would become fluidized. An anaerobic area develops in the middle of the sandbed instead of at the bottom. It is believed that the most effective form of denitrification occurs roughly an inch below the surface and that below this the bacteria do not recieve enough nitrate because the bacteria above it have used it. With an upside-down sandbed you only have an inch or two of denitrifying bacteria however it is located in the middle of the bed and the bottom of the bed becomes aerobic instead of almost dead space like a regular DSB.

[daytonians]

ChinChek,

I was not referring to phosphate or nitrate. The low oxygen and no oxygen areas of a sand bed convert nitrates into a gas called N2. This is a highly toxic gas, but it is normally released in very small amounts which quickly bubble to the top of the water column and exit into the air. This is why it can be catastrophic to stir a deep sand bed. The stirring can release a large amount of the gas.

Many people believe that under-gravel filters allow this gas to build up and then be release in large quantites all at once. That is why they have fallen out of favor with reefers.

My fear with the upside down sand bed is that it would do the same, if there is not enough flow. Or, not allow for low to no oxygen zones if the flow is too fast. Without the anarobic (no oxygen) zones, the sand would be turning amonia into nitrate, with no way to convert the nitrate to N2.

[Cody Ray]

<a href=showthread.php?s=&postid=7853945#post7853945 target=_blank>Originally posted</a> by BeanAnimal
My intent was not to be rude. And I did mistake you for the original poster... if I can edit the post I will...


EDITED

Great now my post makes no sense ;)

[Cody Ray]

<a href=showthread.php?s=&postid=7856033#post7856033 target=_blank>Originally posted</a> by daytonians
ChinChek,

I was not referring to phosphate or nitrate. The low oxygen and no oxygen areas of a sand bed convert nitrates into a gas called N2. This is a highly toxic gas, but it is normally released in very small amounts which quickly bubble to the top of the water column and exit into the air. This is why it can be catastrophic to stir a deep sand bed. The stirring can release a large amount of the gas.

Many people believe that under-gravel filters allow this gas to build up and then be release in large quantites all at once. That is why they have fallen out of favor with reefers.

My fear with the upside down sand bed is that it would do the same, if there is not enough flow. Or, not allow for low to no oxygen zones if the flow is too fast. Without the anarobic (no oxygen) zones, the sand would be turning amonia into nitrate, with no way to convert the nitrate to N2.

Unfortunatly you have mixed up 2 different gasess created by the sandbed. N2 (nitrogen) is completely harmless, it comprises 78% of the earths atmosphere. You may of been thinking of sulfur, which is also harmless http://en.wikipedia.org/wiki/Sulfur_water

The reason sulfur would accumilate in the UGF was that it was attempting to rise while the water was being pulled down. In an UDS (upside down sandbed) the water is moving upward in the same direction as the sulfur would want to. It could actually help prevent sulfur from building up in the sand. I havn't read any actually proof that sulfur itself is harmful at the amounts found in a sandbed.

[yeame]

ok im back from vacation and I should have said RFSB or DSB.
it is my understanding that a DSB is pointless unless you have a plennum. (because of system crashes)with my 75g I have the under gravel part of a under gravel filter this lets me clean under the sand every 5-6 months the only water changes I do if that.
the tank is allmost a compleet ecosystem and it has no sump! just a fluval 404 filled with rock rubble and an old wisper 5 hob filter and 2 power heads to move water threw the 175 pounds of live rock there is about 150 pounds of mix substrate and a cheep lee's air driven skimmer that some how produces only phyto that I feed to my sps tank.I no longer feed my 75g with 9 fish I had 10 but found my 8"sohal tang a new home in a 240g he was 1 1/2" when I got him 4 years ago, I only feed the anenome's(all 4 of them) frozen fresh shrimp,I have 3 large sand sifting stars and probably 10 sand sifting cucumbers all very happy.(my 75 has bin running about 5 years) now having said that when people say it cant and won't work I tend to disreguard any statement they make.
I am in the process of moving the tank into my new 125g and dont want to lose the room with a DSB. I am planning on a few diferent substrates in 2-6g buckets(crushed,coraldolamite,argonite,) with screens and a 1" gap seperating the substrates and the last layer with a mix of all the substrates. the water will flow out of the main tank 1/2 into a 20g long low light tank with mushrooms and a few other low light corals then into the bucket with the other 1/2 of the water then into the sump with LR and a small amount of argonite (so the pods can breed) then the skimmer then bucket of bio- balls then into 33g sps tank and finaly back into the 125g tank.
I know BIO-BALLS ( it will be OK!) they wont create a trap being the last part of the filter insted of the first just a place for pods to hang out with good bacteria.
and now my problem do I run a remote DSB, or reverse flow sand bed ?

[outy]

you asked that question already.

it seems your kind of set in your ways and missinformed ,,[a dsb does not need a plennum] your set up is so different from the normal known to work kind of aquarium that your the only one who can answer your own question.

[daytonians]

Sorry, yep I said N2 but ment sulfer. Many reefer have had a old sand bed get disturbed and lost corals and fish because of it. It probably takes a lot of disturbence to be a problem, such as a powerhead coming loose and getting directed right at the sand.

Do a search and you can probably find threads about it. I'm too cheap to pay for a membership, so I can't search.

Nitrogen is not harmless. Corals will not survive in tanks with high Nitrates. They do not harm fish as far as I can remember though. The whole purpose for a deep sand bed is to eliminate nitrates and nitrites.

[Cody Ray]

<a href=showthread.php?s=&postid=7871713#post7871713 target=_blank>Originally posted</a> by daytonians
Sorry, yep I said N2 but ment sulfer. Many reefer have had a old sand bed get disturbed and lost corals and fish because of it. It probably takes a lot of disturbence to be a problem, such as a powerhead coming loose and getting directed right at the sand.

Do a search and you can probably find threads about it. I'm too cheap to pay for a membership, so I can't search.

Nitrogen is not harmless. Corals will not survive in tanks with high Nitrates. They do not harm fish as far as I can remember though. The whole purpose for a deep sand bed is to eliminate nitrates and nitrites.

and turn them into nitrogen, which is completely harmless :D

[yeame]

first off I never said a DSB with out a plenum wouldnt work I said it is pointless. that is if you plan on having your aquarium more than a few years because of the build up of hydrogen sulfide in the sand bed witch will result in a systen crash. (been there done that ) here is some reading for the missinformed and anyone who wishes to learn about a DSB and a plenum if some one knows a site like this for a reverse flow system please let me know http://www.advancedaquarist.com/issues/sept2002/feature.htm

[BeanAnimal]

yeame... this has been hashed out dozens of times. Suffice to say that there are dozens of long term DSB setups without plenums that have not crashed and do not have hydrogen sulfide problems. I hardly think that you are an authority on DSBs, and one online source does not prove a point. I recently helped take down a long established 500 gallon system that had a DSB (owner purchased a new home and had to move). There was certainly no obvious oder of trapped hydrogen sulfide relased when we tore the system down and scooped out the sand. I was amazed at how little smell there actually was.

What was the question here? Did you have a question about remote DSBs or are you trying to start a DSB crash thread?

[outy]

first you need to read the article you wish us too. before you come in here with a statement like [a DSB is pointless unless you have a plennum] you had better do some homework. i have.

the jaubert method has nothing to do with a DSB at all. its set up to be a live sand and very coarse at that,,, most would call it a gravel bed. not only that its very tempermental at best and failure is almost certain unless you follow jaubert,s methods to the T. jauberts methods have been around for 20 years [he worked on this allot before his french patent in the late 80,s]

we are beyond his methods as there are far better ways to deal with a closed loop in a lightly stocked tank.


[Professor Jean Jaubert of Nice University first perfected the living sand method of enhanced biological filtration, a process that received a French patent in the late 80's followed by a US patent in 1991. ]

yes his tanks have seen great growth and they have been up and running for a long time but at what cost

[The physical and chemical parameters of each tank and its technical equipment is monitored 24-hours-a-day by a computerised management system.]

[ The high esteem in which the Monaco Aquarium is held rests firmly on these exhibits, which thrive thanks to Jaubert's Microcean process and the expertise of the technicians and biologists of the aquarium.]

i said it before and i will say it again, this type of system is like tuning a carburator and 1 small error and you will crash hard.

in final. his old method is great in a labratory but for the home aquarium/sump/fuge it is not practical with so many tried and true methods of nitrate reduction avalible

[yeame]

looks like you are thinking to hard are you talking about the jaubert system or the monaco system or mixing the two there is three different systems in the artical I posted the link to having said that get over the whole DSB debate I dont realy care I want to know about a remote dsb and a reverse sand bed neither of which are in the main tank and neither are lighted and I cant find much on the reverse sand bed if any one knows anything about the reverse sand bed let me know and OUTY you need to read the article again

[BeanAnimal]

yeame, I think your qeustion has been answered. Fill a 5 gallon pail with sand and run water over the top of it, brisk enough to keep detritus from settling, but not brisk enough to erode the sand.

The lack of light will keep algea from growing and the DEEP sand will have a very long life. It is a very simple system and easy to take offline or replace if there are problems. The unit does not need a host of fauna and sifters like a local bed, as there is no light and nothing fouling it. There is no tweaking and no twiddling. The unit is not affected by power outages or other mistakes.

The "upside down" bed can be looked at many different ways. There is a lot of tweaking of flow and other parameters and frankly it may or may not work as expected depending on any number of ever changing variables. Why bother with all of the trouble when such a simple solution is available?

[outy]

my friend the only person to do a reverse live sandbed successfully for a long period of time is jaubert, everyone else gave it up already because of failure...

the jaubert method and the monaco are one in the same.

[ Since Jaubert's work is featured there, his system has come to be called the "Monaco System"]

[Jaubert's Method, the "Monaco System," Defined and Refined] the title of the article.

there is not 3 different systems there is only 1, obviously you do care about the dsb debate because you wont let go of a failed idea that 1 proffesor in a lab got to work.

[Cody Ray]

As far as I know it isn't so much of a "failed idea" as it is pointless to use a plenum because the denitrifying abilities of both a plenum system and a DSB are pretty much the same. IMO the reason most people failed with a plenum is because they placed liverock on top of the crushed coral. Thoughs areas didn't recieve enough flow and collected detritus faster. With the sugar fine sand used in a DSB it is more difficult for detritus to sink into the sand.