Algae Scrubber Advanced
 

We have on this forum (imho) an excellent thread - Algae Scrubber Basics - created by srusso (thanks man!). Now I think it could be wise to start a thread about the more advanced topics in Algae Turf Scrubbing.

For the theory as it stands, all basic questions, designs and other basic stuff about ATS, go HERE.

Since I'm an avid aquarium DIY nerd, and have been for 20 years, I recently jumped on the ATS-wagon to see what it would do for me. So far I have experience from five different versions. Versions that are open, closed and with CFL, T5:s as light plus all sorts of different media to grow the algae. One could say there are as many versions as there are people scrubbing.

One thing is for sure - this is a method that not many people use compared to other more proven methods. Maybe it will rise in popularity in the future or maybe it will be forgotten over the next "flavor of the month". But I think it's time for a collective scientific approach. I think we need to discuss and try out different methods and approaches to scrubbing in a scientific way to see what is good, what is bad and where this method can be refined.

One might look at the open source movement of GNU / Linux - They have enjoyed tremendous success due to the fact that they work as a collective (well mostly) all over the world. I think we have an opportunity to do this as well. Crowd-sourcing to gather data, draw conclusions and figure out solutions to problems.

Some topics I think could be included in this thread:

* How can we be scientific about ATS and provide empirical data to draw the correct conclusions?
* For what kind of tanks can an ATS be beneficial or dangerous?
* Light sources - can LED be more than experimental for ATS?
* Skimmers in cooperation with scrubbers - Advantages and disadvantages.
* Scrubbers and carbon dosing - Competition or cooperation?
* Approaches to achieve 3D-scrubbing in both open and closed designs
* Ozone and UV combined with an ATS - good or bad?
* Effects on livestock - Good and bad
* Long term usage of an ATS and how to collect data about it?
* How to avoid crashes - what are the safeguards?

This thread is NOT intended as a "it doesn't work" *flame on* kind of thread. If you wish something like that, please start your own thread and watch it go down in flames. (pun intended) :love1: Also, English is not my native language, so feel free to correct my language, spelling and such.

Let's get going! :wave:

I think photoinhibition would be interesting to look at. Everybody seems to run their scrubber lit for 18 hr a day. Maybe in some setups this is ideal. I suspect that with intensely lit scrubbers this is not the case. An O2 senser plumbed to the scrubber drain would reveal what is going on.

I think two scrubbers where only one is lit at a time would be the most efficient use of electricity. Use the O2 senser to determine when photoinhibition begins and set a light timer accordingly. So when photoinhibition begins the light goes out on that scubber and the other scrubber gets lit up. On the runup to photoinhibition, growth is fantastic, then growth drops like a rock, no matter how much light (electricity) you throw at it.

I base my opinion on this link http--www.int-res.com-articles-meps-134-m134p207.pdf

It is a study of Cheato, but it is mentioned that most marine algae behave in a similar manner.

Ive read a similar idea, so on my scrubber I started to run my lights on 4 hour intervals off for 4 hours, I have since raised it to 5 and 3 and It seems to get a little better growth now. But since this thread is being started maybe I should start adjusting the light schedule and measuring how much growth I can get with each one. And where would we get an 02 sensor for saltwater?

Kind of pricey, but here.

http://www.marinedepot.com/American_...TEMOID-vi.html

Hmm, thanks for the link. Now how to get it to graph the 02 level.....hmmm I wonder if a small PLC would do it. Ive been contemplating integrating a PLC into my tank. Ok time for some more research. Thanks Joe

Just curious, what kind of lights do you have on your scrubber? The reason I ask is, unless you are running something fairly intense like T5s at point blank range, it might be a waste of time to try and find when photoinhibition occurs.

Im running the 4 total 23 watt cfl's. You think that with these lights they will never reach full photoinhibition? would LED's work better?

This is very interesting. I have been thinking about running two scrubbers - but that has been to get a more even export (cleaning one on Wednesday and the other on Sunday) than I get now. Photoinhibition is another good reason. Currently I run all my scrubbers on 24W T5 @ 3000K but have been thinking on trying out 10W powerled modules.

I don't know. If it were me, I would not spend the money on an O2 sensor if I were running cfls.

I also would expect rock solid steady PH with alternating scrubbers.

Thank you very much, and I must say an excellent start to this thread!! Well said, and you should be proud of your english, as it is eloquent and well stated. Better than my own...

While they may not be ideal, I do get a decent amount of growth with them and if I move them to close it will turn the algae yellow. I know I could get better coverage with t5's or LED's so I might look into a cost/benefit analysis. And running a 02 sensor would help prove what light is best and if CFL's are sufficient.

If someone has time to skim or should I say "scrub" the basics thread of any useful posts that help here. I know myself and others have posted some great info that relates, I wish I could but don't have the time at the moment.

Could I use an ORP probe to get a good data for photoinhabition?

Randy explains in this link how ORP works, and I know my apex can take this probe. I could began to possibly provide some relevant data. I haven't yet read the link you provided about photoinhabition so please excuse my ignorance on the topic.

If so I will purchase the probe as soon as I can.


http://reefkeeping.com/issues/2003-1...ture/index.php

From what I gathered from the first part of that article, probably not.

I was initially thinking that there's no way this discussion is going to fly on this site. Everyone who wishes to discuss this, on both sides, needs to be on their Ps and Qs. I personally don't have a ton of free time to dig up data so you may not see me posting on here a lot. But I'll follow it...and we'll see how it goes!

I can give it a try later on. I have read EVERY post in that thread. Lots of good information in there!

Exactly!

As was mentioned in the basics thread, I am working on setting up a controlled experiment using multiple independent (and isolated) systems using various LED combinations in an attempt to 1) pinpoint the optimal growth spectrum and 2) monitor nutrient uptake. #2 is really secondary, but since it only minimally impacts #1 to sample and test water, why not (gotta do it anyways). There may be other pertinent data, but mainly I am working on this to try and pin down the spectrum issue, as it seems there has not really been any study to date that really shows the optimal artificial spectrum for growing algae for our purposes.

It may also reveal the dominant type of algae grown under each given light source, or combinations of light sources, as well as the efficiency of said algae.

Should be interesting. If I have the time, I'll periodically post about the experiment, but the detailed thread about it is not on this site.

I can only offer my experiences with this as "proof", but due to a lack of outlets I run my lights 24/7. During the scrubbers intitial breakin period of 4-5 weeks the algae grew like crazy and I got enormous amounts of stringy growth on the screen.

Now after almost 2 years of the same 24/7 schedule the results are obvious. The algae is very thin and weak. Also there has been an increase in DT algae in certain areas. IMHO this is a very important part of the ATS that really needs to be followed correctly for long term success.

Cardinal rule violation! You need to run 18/6. Everything needs dark time. Get a shorty extension cord and a timer. Also have you been replacing your lamps?

As far as tuning a scrubber, I would look at factors that limit growth, and do not think a well aerated tank would have a O2 deficiency.

I suspect limiting factors to growth are light, nitrogen, phosphorous, flow rate, and surface area and possibly micronutrients.

When I set up ATS originally I used iron gluconate to test whether micronutrients were a limiting part of algae growth. It appeared it was. I then widened slot and and put in larger pump, and again I suspect flow rate limits growth.

Another issue I am concerned about if nitrate limitation would lead to cyano in display tank. However this may be overcome with adjusting other factors such as light levels or flow rates.

In freshwater planted aquarium, a standard recipe is used to easily grow vascular plants.

1) adjust CO2 levels to 10-15 ppm by injection and controller.
2) add micro nutrient mix for 2 weeks to remove this a limitation
3) add mixture of Potassium chloride and potassium nitrate, maybe 2:1 to reach 5-10 ppm nitrate. Will remove blue-green algae when present.
4) spike phosphates when symptoms of phosphate limitation are seen.

For reef tanks, I suspect iron gluconate may infact also intially lead to cyano. For corals I also much prefer to feed more. instead of add nutrients as organisms are heterotrophic.

I know, i know. . . lol. Kind of embarassing to admit that :uhoh2:

Its a physical limitation, I just dont have any more outlets. I am going to have to come up with something though. . . also, yes the lights get changed on time. Every three months when I change the chemipure.

Head to walmart,
For a few bucks go buy a power strip. If you don't have space for a power strip, get an outlet splitter. It's designed to turn a standard pair into six outlets. Even comes with screws to replace the face plate of the outlet. Also if you have a lot of D/C adapters you should grab some short 6" extensions, so you are able to get full use of all outlets. And most importantly grab your self a indoor/outdoor timer... Plug a power strip into it... You could get everything you could need for less then $20.

Thank you for being honest.

Not as experienced as you guys but I have been running my scrubber for 2 years now. This thread sounds interesting to me. I did notice something interesting last week. I have been running a calcium reactor for 2 weeks now and have noticed a great improvement with my growth. This is obvious why, but I don't know what the longterm affect would be on my system with my scrubber growing more. Meaning possibly taking up too much nutrients. On one of the comments earlier, can you just turn off one side of the scrubber lights and leave the other side on and alternate?

Interested to see what the O2 sensor info is going to provide.

Interesting to hear. I have heard and also experienced this about the growth getting improved by either a reaktor, kalkwasser or ca/kh additives being added.

I just learned that if you have low CO2 due to high scrubber algae growth, then the algae will start assimilating bicarbonate (alk) instead, but I haven't heard anything about growth affecting calcium uptake.

specifically:

Hopefully some algae experts can tune in here to give some perspective.

Here is my PAR reading from my CFLs to my screen.

226 at 4" and 302 at 3"
Attachment 151803

Used my fish net to push my hanging light an inch closer.

Attachment 151804

FYI I did push the screen back to account for the 1" sensor width.

Bulbs are two months old.

I hang them horizontally which creates a more even light coverage. This corrects "hot spots" on algae screens when the CFL is pointed at the screen. Unfortunately or fortunately (depends how you look at it.) this puts 100+ PAR in my sump which has created wonderful place for mysis, pods and worms live undisturbed.

This would be awesome, just started looking into this instead of going the skimmer route and reading 70 pages could give me a headache :lmao:

Is it Par that you are seeking or levels of particular spectrums? What is the spectrums that most algae goes at?

Built-in Chiller?
 

Maybe this isn't the spot, but...

I've been reading about Chillers (Had the Dorm Fridge idea stuck in my head and it's really good that I did some reading!).

The thing I've tripped over a number of times is using evaporation to chill, 8,000 BTU per gallon evaporated, "they" (we?) say.

So, is it safe to say that an open Algae Scrubber, say 26" long by about 12" high, running in open air, is a good chiller solution?

I seem to run up to about 80 degrees inside the house during the day, and the 90 gallon test tank I have runs itself up to a frightening 84 degrees (maybe more if I leave the lights on! :eek1:).

On the "real" 220g tank I'm setting up (with a scrubber), my sump is in the basement and the scrubber would be working in basically 65 degree air all the time. There's a 3/4 HP return pump and I'm going to run three 175W halides + some fluorescents to start, right over the water, but separated from it by... something... (working on that now).

Think the evap from the scrubber (+ 30g open scrubber sump, + 120g open sump tank) will work?

Think this'll work?

In short, yes. Even better, put a fan on it. You will want a temp controller because an open-air screen with convection will drop your temp very well.

just to be clear, you're running the MHs and Fluorescents where?

Lights are over the display tank. Just mentioned them as the heat generators in the system (waste heat generators, that is)

Reading his post and writing my reply in my head as I read, you wrote almost the exact words I was going to type.

+1

We all know that an ATS can allow us to significantly reduce our water change frequency. This is a touchy subject that a lot of people feel strongly about and the above statement is usually followed by the disclaimer stating that this is if the purpose of water changes is for nitrate reduction.

The major reason for an ATS system to get periodic water changes would be to replenish trace elements and such. I was wondering if anyone had thought about developing a DIY food which would naturally contain such trace minerals. I would think that if you could feed your tank with such a food you could maintain your trace elements through feeding and further push out your water changes. I understand you can buy supplements and dose your tank accordingly but this is just something I have been thinking about.

This is exactly what I do. Rod's Food is great because it's a total tank food. My local club gets together every 6 months or so and makes about a 3 gallon batch of DIY food that contains various seafood, off-the-shelf fish food, and coral foods like Cyclopeeze, Reef Chili, etc. It's essentially a DIY version of Rod's.

I don't do any PWCs unless it's a last resort, like one of those 'gut' feelings, like I notice something odd and I default to doing a water change to see if it helps (which, so far, it has made no difference)

I would warn about taking a type of filtration as a sole ideology. Salt water parameters are measured by basic parameters. Some would argue that not doing any water changes will cause a closed reef tank to crash hard eventually. MudShark is one of the few TOTM examples I ever saw that was excellent condition. He eventually moved away from technique. I run Skimmer and scrubber. Scrubber product is negligible.

ATS will remove inorganic nitrogen and phosphates with ease however.

As far as trace elements go, if you choose to use them, I like the idea of using only elements that are known to deplete readily. The ones that depleted readily can also lead to excess algae growth. I have tried Iron Gluconate, Potassium Iodine, and Potassium Sulfate. I would like to have evidence if ATS can deplete potassium like vascular fresh water plants do. I am currently using a little TLF Sea Elements. I am not a fan of control bleaching experiments like Zeovit personally. It looks risky and unnatural.

I have enjoyed results of scrubber over last 9 months. Cyano faded and hair has made a very slight come back. I will just use a few herbivores as I got away with just snails in last 9 months. Coloration and maintenance are easy and will keep running it.

I understand the debate on filtration ideology and I understand it is not without risk. I also don’t want to suggest one method over another or even say the method I use is better or worse than another. What I want is to see how far this technology can be pushed and where its limitations are.

My tank is running with a scrubber as its only filtration and I know there are proven methods available that work well and produce beautiful reef tanks. For me I like the excitement of doing something different and the experimentation that is involved.

Anyone wish to share how long they have gone without a water change on their scrubber only filtered tanks? Has anyone had any problems or any lessons learned?

What do you mean by limits? Bad growth, crash, algae everywhere?

There is a fundamental limit to the amount of algae that can be grown on a screen of given size with given flow and given light from a given source. Word of the day: given :spin2:

As far as limits go, many of them are generally assumed based upon anecdotal data, but not many have been truly (scientifically) tested. Such as the upper limit of copper presence before algae is killed or growth/filtraion is hindered, actual uptake rates of certain nutrients, I could go on but you get the general idea.

I do know that someone did carry out an experiment of sorts to see what effect iron dosing had on growth. It went so far as to dump an entire bottle (I think 500mL) of Kent's Iron/Manganese into a 90 gallon system in one shot. This resulted in a lot of coral mortality, but it gave insight into the scrubber's ability to handle such a large dose. Not scientific either.

Some of these things are tests I might try to perform once I get finished with my LED experiements.

One of you guys mentioned carbonate intake by ATS. My ATS was working ok for 2 yrs. I finally added a Ca Reactor 3 months ago. I noticed immediately that my GHA was growing at an alarming rate. What I noticed was that my Alk readings stayed about the same but my Ca numbers were slowly creeping up. From 400ppm to about 415-425. Everything else staying consistent. Like you guys are saying. Provide more nutrients and your ATS will work better. My calcium reactor effluent dumps before my ATS intake pump. Hope this contributes to any helpful info for you guys.

Psyops; Wait, the GHA you're referring to is your ATS GHA? So this is good right?
That would mean for more GHA to grow there is going to be more N and P uptake.

Just curious as to what peoples take on the idea of using an ats for filtration for breeding. In a breeding setup, lets say for clowns, there is a large amount of feeding going on a large amount of waiste. And there can be a large turnover with fish entering and leaving the system. Plus were talking about growing fish from eggs to adolescents. Does anybody see any issues with an ats interferring with the growth of fish. possibly uptaking too many nutrients or the wrong nutrients that can affect growth in fish. This idea seems like it would be great for a fish breeding system. Just trying to get other peoples opinions to make a good decision for my application.

I would think an ATS would be ideal for breeding. Large nitrate excursions should be handled in stride. You'll probably be getting some pods into the water column that fry would love.

Just following along... :)

Someone earlier asked about doing water changes when running an ATS. I don't do them in my 240g mixed reef. I do however add ALK, CAL, Mag, Lugol's, SeaChem Reef+ and top-off with Kalk. I've been doing this now for about 4 months and have had good success. I also use Phosban when my PO4 levels start to creep up.

Kcress; yes ATS GHA. My Ph is around 8.15-8.22. I guess maybe I have too little CO2 so myATS is using up carbonate. I agree, it is a good thing. My system is healthier as a result, but I dose soda ash in my top off water to keep the Alk around 9. If you have any other ideas on what I could do to maintain alk please let me know.

Kalk... In your ATO... Both Kh and Ca

I don't need Calcium. My levels are ok from the reactor. Our guess is it's probably the carbonate is beng taken up from the ATS. But thanks for the input. Don't want to minimize your comment by any means. My calcium levels are actually gone up a little.

I also forgot to mention that my Skimmer air intake is from outside. It makes sense that maybe I would have less CO2 in my system. I guess I can experiment and have my skimmer intake from inside the house. Too chicken to change things at this point.