Algae Scrubber Basics

[michael_in_nc]

Great thread. I've been reading through this and I apologize if this has been answered through out the thread, but I had a few questions. I am currently building a large tank (250G) and I'm interested in the ATS. I plan to start with a skimmer since it's what I know, but try and experiment with the ATS to see if it's for me.

1. Any disadvantage to using both (skimmer & ATS)? Seems like the skimmer pulls alot of the organics out and the ATS can help reduce nutrient levels better than the skimmer alone.

2. What about refugiums and ATS? Refugiums provide other benefits, but it seems like nutrient export would be one of the key ones at least from my perspective. If I was only running a refugium for nutrient export, would it help to keep it with an ATS?

3. What about carbon dosing? I saw something about carbon dosing reducing the growth rate. Seems like the carbon dosing is really just reducing the nutrient level and keep the growth rate slower on the ATS, but it's still helping export residual nutrients?

Thanks for the inputs!

[dogstar74]

1. No problem using skimmer and ATS, I believe the ATS will pull out the things that the skimmer misses.

2. ATS will out compete refugium. The micro algae will outcompete cheto and gradually starve it out of exhistance. If you wanted to make a softy and sponge refuge, then I'd say go for it.

3. Carbon dosing uses denitrifying bacteria and requires a very powerful skimmer to reduce NO2 by physically removing the bacteria that use the NO2. I believe a decrease in NO2 may choke out the ATS and make it less effective or obsolete. But the problem with Carbon dosing is the measuring, the constant fiddling with the levels, and the threat of a crash due to a biomass bloom. These risks don't exhist with an ATS working properly.

HTH
Aaron

[Floyd R Turbo]

dogstar, very good explanation #3. But are you talking about Nitrite (NO2) or Nitrate (NO3)? I'm not very familiar with carbon dosing....

[dogstar74]

Oops, been a long day.

Nitrate, forget the nitrite.

Thanks

[kdirk]

Anyone run bio-pellets in a reactor with a scrubber?

[michael_in_nc]

Originally Posted by dogstar74

1. No problem using skimmer and ATS, I believe the ATS will pull out the things that the skimmer misses.

2. ATS will out compete refugium. The micro algae will outcompete cheto and gradually starve it out of exhistance. If you wanted to make a softy and sponge refuge, then I'd say go for it.

3. Carbon dosing uses denitrifying bacteria and requires a very powerful skimmer to reduce NO2 by physically removing the bacteria that use the NO2. I believe a decrease in NO2 may choke out the ATS and make it less effective or obsolete. But the problem with Carbon dosing is the measuring, the constant fiddling with the levels, and the threat of a crash due to a biomass bloom. These risks don't exhist with an ATS working properly.

HTH
Aaron

Exactly the explanations I was looking for. Thanks!

The carbon dosing seems very "touchy" to say the least and not as "natural" as the ATS. I have a lot going on now with the new tank setup but I'll be back to check my ATS plans here before building.

[Floyd R Turbo]

Originally Posted by kdirk

Anyone run bio-pellets in a reactor with a scrubber?

This is answered above by Dogstar in #3. Just for those other interested in bio pellets, I'm by far no expert at all but here's the relevant product description:

How Biopellets Work:
Biopellets are composed of biodegradable polymers designed for use in a fluidized filter. The pellets promote the growth of aerobic and anaerobic nitrifying bacteria which use carbon from the pellets to consume nitrate and phosphate. This process dramatically eliminates unsightly algae and cyanobacteria (red slime) while increasing the overall health and vigor of the tank’s inhabitants.

The surplus bacteria generated by the biopellets are then consumed by sponges and corals or removed by a protein skimmer. Within a few weeks, without any routine dosing, even the most novice reefkeeper is left with a crystal clear tank.

So it is another form of carbon dosing

edit: just a reminder that we want to keep this thread on the topic of the basics of algae scrubbers: designing, building, maintaining, troubleshooting. We just don't want to go off too far on a tangent about other filtration systems and why or why not to use them

[kdirk]

Using bio-pellets in a reactor is not the same as vodka dosing. The reason I'm asking is because my ats is not out competing my display.

[Floyd R Turbo]

It is a form of carbon dosing though, ust a different form. Thus the end result is the same. Carbon dosing of any form has shown to be detrimental to algae growth. However I should note that the purpose of ATS and bio pellets appears to be the same, reduction of N and P to choke out algae, so if neither is working, something else is a foot.

[kdirk]

Ya I'm not sure whats going on, every Sunday i clean my screen thats full of algae. It doesn't seem to starve the display at all. So i was thinking of doing the pellets until its mostly gone then let the scrubber take back over.

[Jukka]

I used to have various carbon sources + ATB Supersize skimmer as filtration for my 400 gal reef. I never succeeded to outcompete nutrient problems with those, no matter how much carbon I added. I also tried the pellet version.

Since building a large scrubber with lots of light, all problems are gone .

But I didn't take the skimmer out of the system and didn't stop carbon dosing, and don't intend to.
I just reduced carbon amount to about 1/10 of the original. I like the effects carbon does for fungi, and other stuff like that, growth.
Though other reason for keeping skimmer online is the amount I paid for the supersize ATB...

[travis32]

Well, I got the new screen only with my ATS.. When I pulled the old ATS. I scraped a lot of the algae off and instead of letting it go down the drain I hand smeared the film algae all over the new screen (after it was roughed up.)

I then cut out 4 or so 1-2" X2-3" pieces of the old screen and zip tied them onto the new screen as others suggested. The screen where I smeared the film algae is really taking off just after a couple days. It's probably half way to being as populated with algae as my old screen.

I agree with others that so far my screens (either this or the old one) were unable to outcompete my display yet. I even have my halides reduced to around 8-9 hours a day that they're on. not the typical 10-11. I have VHOs for actinics and they're on close to 10 hours.

The good thing is most of my HA is died off or limited to a small patch here and there. Mostly dead. However Bryopsis is everywhere and shows no signs of receding. Not neccessarily expanding. Though it does grow back if I pull some of it. Hopefully with the new screen within a couple more months the bryopsis will also be receding.

[srusso]

Originally Posted by kdirk

Ya I'm not sure whats going on, every Sunday i clean my screen thats full of algae. It doesn't seem to starve the display at all. So i was thinking of doing the pellets until its mostly gone then let the scrubber take back over.

First please post pictures of your ATS, let us know size of screen, lighting used, DT size... etc

A picture of the tank is always nice.
We really love to see before and afters!

additionally, how long has your algae scrubber been running? where does the algae in the DT grow? Is it just on the rocks? Just the sand? Or glass? Or does it seem to cover any lighted surface?

You may have already posted all this stuff but we have helped a lot of people on this one thread and it's becoming hard to keep track of everyone.

[srusso]

Originally Posted by travis32

Well, I got the new screen only with my ATS.. When I pulled the old ATS. I scraped a lot of the algae off and instead of letting it go down the drain I hand smeared the film algae all over the new screen (after it was roughed up.)

I then cut out 4 or so 1-2" X2-3" pieces of the old screen and zip tied them onto the new screen as others suggested. The screen where I smeared the film algae is really taking off just after a couple days. It's probably half way to being as populated with algae as my old screen.

I agree with others that so far my screens (either this or the old one) were unable to outcompete my display yet. I even have my halides reduced to around 8-9 hours a day that they're on. not the typical 10-11. I have VHOs for actinics and they're on close to 10 hours.

The good thing is most of my HA is died off or limited to a small patch here and there. Mostly dead. However Bryopsis is everywhere and shows no signs of receding. Not neccessarily expanding. Though it does grow back if I pull some of it. Hopefully with the new screen within a couple more months the bryopsis will also be receding.

Travis, if I remember correctly you setup your ATS about 2 months ago. Right? It will take some time for everything to go. Your tank is always attempting to balance itself. Now that the hair algae is gone it will make way for another algae to grow in it place. The reason the hair algae is gone is b/c it was no longer able to sustain growth/life, however this is not true for the byropsis, until of course the ATS chokes that out. This may lend itself for yet another algae to grow that finds that location habitable, until the fuel source in that location has been depleted. It's going to take a little time before you see complete results, but it will happen.

Oddly it works a lot like fossil fuel... Once we drill all the oil we can find... We're right back to the stoneage...

[ecomdesign]

I've read through the first 30 or so pages and I really like what I see. Thanks to all of you! Patenice has gotten the better of me though and I want to start a plan as I continue to read the rest of this thread.

Can I ask why no one has done a design similar to Floyds, but in a vertical layout instead? From my understanding it would take less GPH to run making it more hydro friendly. If I were to build a vertical unit using T5HO, is it ok to run the bulbs vertically too?

[maglofster]

Originally Posted by kdirk

Anyone run bio-pellets in a reactor with a scrubber?

Yes, in two tanks. But in one tank I have now removed it since it seemed to directly compete with the ATS with slower growth as a result.

[TheFishMan65]

Since they are both trying to use nitrate and phosphate they do compete. I have heard the pellets will win (same principle to get algae out of the tank). But maybe with the added light of an ATS it might have a chance.

[travis32]

Thanks Srusso, yes, it's roughly 2 months now. My skimmer is pulling very dark skimmate, so, I know that everything's working as it should. And it is 125g of water and rock that went through a very large die off, so, I agree, it may take another 6 months for good results.

So, would water changes speed the process? I know they are generally frowned upon when running an ATS. Or at least not viewed as neccessary on a routine basis. I just know that my Macro - hair and/or briopsis usually goes through a period of die off when I do a 30 gallon water change. I'm not sure why other than maybe a sudden reduction in phosphates? Then the phosphates leach back in from the rocks and the algaes grow back?

If that's the leading principal, then a water change would impact the ATS negatively initially, but, the ATS would potentially have first dibs on the new nutrients leaching from the rocks, leading it to possibly having a sudden growth, out performing macros growing back in the display?

Also, I noticed coraline growing on the side of my Acrylic ATS box. (not the lighted sides)? I assume that's o.k, it may become my natural light blocker since I didn't have the unlit sides painted black...

[srusso]

Originally Posted by ecomdesign

I've read through the first 30 or so pages and I really like what I see. Thanks to all of you! Patenice has gotten the better of me though and I want to start a plan as I continue to read the rest of this thread.

Can I ask why no one has done a design similar to Floyds, but in a vertical layout instead? From my understanding it would take less GPH to run making it more hydro friendly. If I were to build a vertical unit using T5HO, is it ok to run the bulbs vertically too?

I have never tested this myself, and I am simply regurgitating what others have discovered. The longer the scrubber is the better the scrubber power. If your screen is turned the other way you will get a more uneven growth and becomes top heavy.

A logical reason I can think this happens is the algae that comes in contact with the water first gets its fuel first. Leaving less for the bottom to grow. In the case of a scrubber that is 10" vertical vs 15" vertical, I dont think you would see the difference. But I think it would show exponentially more on a 36" long vertical scrubber.

The other obvious reason being less GPH = less water contact... yes the water that does get scrubbed gets cleaned, but less water is being processed.

Lighting doesn't matter if vertical or horizontal.

[srusso]

As for the bio pellets, Floyd explained this...

My very basic explanation is, bio pellets do nothing different then what bio balls did... give a medium for beneficial bacteria to grow. The more bacteria the higher reduction of N and P.

So its from my understanding its not a matter of win or lose. Which do you want to use, if you use both understand your going to do one thing... reduce N and P. If you have none the algae will not grow. Just as if you don't replace your bio pellets as you should, the bacteria will use all the available carbon, once that is depleted the bio balls will do nothing.

It comes down to... IMHO do you want to grow free algae that you scrap off your screen each week or do you want to keep buy bio pellets? The answer is not clearly one or the other but a matter of how much money you have... and which you like better/find easier to maintain

Ps. if your scrubber is not removing all of your N and P on its own, then more then likely you have a build problem.

[Floyd R Turbo]

Originally Posted by ecomdesign

I've read through the first 30 or so pages and I really like what I see. Thanks to all of you! Patenice has gotten the better of me though and I want to start a plan as I continue to read the rest of this thread.

Can I ask why no one has done a design similar to Floyds, but in a vertical layout instead? From my understanding it would take less GPH to run making it more hydro friendly. If I were to build a vertical unit using T5HO, is it ok to run the bulbs vertically too?

Like this?



If you go to the algae scrubber .net site, click the algae scrubber link, the first link will bring to you a page with hundreds of designs, which will take a while to load. This one is about 1/4 to 1/3 of the way down the page.

Like srusso said, the taller screens tend to get to a point of diminishing returns, because as the algae grows thicker and longer (longer mainly) it will layer up and block the light more towards the bottom of the screen. You also have to consider the weight of the screen per unit length as the screen matures, and account for that in a design.

I think the algae at the bottom of the screen would not be growth limited by the available nutrients so much as limited by light blockage. A given volume of water would have to make several passes over the screen to remove all nutrients, so having a longer path (taller screen) would likely allow more nutrients to be removed per pass per unit width of screen, but with less width (and lower flow rate) it would take the same amount of time for a wider screen of the same L x W dimension and same flow rate (per inch of screen width) to reduce nutrients.

I have seen plenty of 24" tall screens with full growth across the whole height of the screen. I would think when you get to greater than 24", you start to lose a little power.

But it should work just fine, and you're right, if you have a 24" tall x 6" wide screen, you would only need 6 x 35 = 210 GPH instead of 24 x 35 = 840. The problem is that most people don't have 24" of space between the top of their sump and the bottom of their tank.

[srusso]

Originally Posted by travis32

So, would water changes speed the process? I know they are generally frowned upon when running an ATS. Or at least not viewed as neccessary on a routine basis.

No water changes will not help much ( IN THIS CASE) its a matter of the algae growing on your rock depleting the available fuel trapped in your rock. Pulling off as much as you can will force the algae to have to grow back, which will force it to use more of the fuel its finding in your rocks.

***IN NO WAY DO WE FROWN UPON WATER CHANGES***

Additionally the view of MOST of the ATS community, finds that in the ONLY in the case of someone attempting to lower N and P through water changes are they not necessary.

Ps. Travis, had to say it, not at you but I dont want people reading what you wrote and getting the wrong idea... but I am sure that will happen anyway

[srusso]

Originally Posted by Floyd R Turbo

The problem is that most people don't have 24" of space between the top of their sump and the bottom of their tank.

Touche...

[TheFishMan65]

srusso IMO you are mixing terminology.

Originally Posted by srusso

As for the bio pellets, Floyd explained this...

My very basic explanation is, bio pellets do nothing different then what bio balls did...IMHO very different beasts. Bio Balls were designed to maiximize surface area to grow what ever bacteria landed and do not need to be replaced. They were designed to go from Ammonia->nitrite-nitrate. The nitrate was then usually removed through water changes. Bio pellets provide carbon and slowly break down therefore needing replacement. The carbon combines with nitrogen and phosphate to form a living bacteria that can then be removed with a skimmer. give a medium for beneficial bacteria to grow. The more bacteria the higher reduction of N and P But only if the bacteria is removed through the use of a skimmer. There is not much bacteria with bio balls.

So its from my understanding its not a matter of win or lose. Which do you want to use, if you use both understand your going to do one thing... reduce N and P. If you have none the algae will not grow. Just as if you don't replace your bio pellets as you should, the bacteria will use all the available carbon, once that is depleted the bio balls if you had bio balls they would still perform the nitrogen cycle, bio pellets would have dissolved.will do nothing.

It comes down to... IMHO do you want to grow free algae that you scrap off your screen each week or do you want to keep buy bio pellets? The answer is not clearly one or the other but a matter of how much money you have... and which you like better/find easier to maintain

Ps. if your scrubber is not removing all of your N and P on its own, then more then likely you have a build problem.

[Floyd R Turbo]

Good catch. I missed that one.