Algae Scrubber Basics

[el aguila]

I have someone in my local club who had an ATS that he started in 2008 probably took it down a year or two later.

He keeps saying that they are very maintenance intensive and prone to crash when the flow gets interupted a little. I am assuming that he did not have enough flow. Can someone fill me in on the history of these and what may have been the problem with his ATS?

 

[redneckgearhead]

I have someone in my local club who had an ATS that he started in 2008 probably took it down a year or two later.

He keeps saying that they are very maintenance intensive and prone to crash when the flow gets interupted a little. I am assuming that he did not have enough flow. Can someone fill me in on the history of these and what may have been the problem with his ATS?

Its hard to say without seeing his design. But to say it crashed because of a little interruption in flow seems far fetched. It would have to be a MAJOR interruption, like a pump quit or got COMPLETELY clogged, without him noticing. If the flow just slowed down it shouldn't cause the algae to die completely. It would slow down its growth therefore slowing down the consumption of N&P. To say they are labor intensive is, to me, far fetched. I spend less than an hour a week, doing my water change (could cut them completely if I wanted) cleaning my skimmer cup and scraping my ATS. I believe a lot of advances have been made in concept/design since 2008.

 

[Floyd R Turbo]

+1

In 2008, more specifically the fall of 2008, when the vertical waterfall concept was blasted all over the place, there were many things that were not done perfectly by many people, thus some 'got it' and some didn't.

I guess I just read as much as I could so that I understood the concept. I put mine online 10/10/10 so that's 2 years later and there was much better information out there upon which to base my design.

Flow blocking sounds like he used crosscuts which are no longer recommended. Maintenance may have been constant tweaking needed since his design may not have been quite that great. That is all speculation though.

All I can tell you is my experience. Over the course of a year, it takes me about 10-15 minutes a week to clean the screen, a little longer to change lamps and perform other occasional maintenance every couple of months, no PWCs out of necessity for nutrient reduction (moved the entire system twice in a 3 day period), and the only major problem I had was when a fish jumped the fence and got sucked onto the pump intake which killed off 1/2 the screen.

I have a 120g mixed reef tank with everything from softies to SPS and I feed the equivalent of between 5 and 10 cubes of food a day. I have no N and low P (it's not zero, but that doesn't cause any problems). I routinely show this tank to local club members and their jaws drop when I explain my feeding schedule and test results and explain how little time I spend on this tank besides looking at it.

For me, it is one of the best concepts I have ever come across, in and out of the aquarium hobby/industry.

 

[redneckgearhead]

Floyd, what where the negative effects of half your screen dieing? Obviously your tank didn't crash. But did you have any algae out breaks or any other negative things happen to the tank?

 

[Floyd R Turbo]

I can't say that anything bad happened. I didn't get a nutrient spike, N maybe rose to 0.1 or something and quickly came back down. P went up to probably 0.25 IIRC then back down to 0.09-0.16 where it has always stayed. The middle portion of the screen no longer grows any red turf but I don't know if that's related. For about 3 months the center of the screen grew very little algae, I attribute this to the algae on the outer edge out-competing the center (where most of the death was). I had also cut feeding back to combat dinos (which was mainly due to clogged powerheads and is no longer a serious problem) so the screen wasn't getting a full bioload. It has since started to grow in much fuller, but still kind of brown with some yellow globby stuff, so I started feeding a bit more recently.

It's all going back to it's original home soon anyways, which will give me a chance to do some more tweaking, I have to re-do the plumbing so it fits in this sump that I just got done building

 

[Gorgok]

I'm still on my first week of an ATS setup i threw together in a couple of hours (including buying the parts) and i would say there is no way this will be more maintenance than the rest of the things going on with the tank anyway. Between twice daily feedings, daily sock changes, weekly skimmer cup cleaning and dosing/testing of various things; a once weekly clean with some brush seems hardly like a big deal.

I don't know if my flow is enough, as its still a very temporary solution, and my lights are sort of hacked into place, but its now 5 days in and the screen has growth on it, small brownish stuff, but growth none the less.

One issue i do have, even though the screen is in my sump, is i have snails (strombus maculatus) feeding on it... Not much hope in controlling them either, there are literally hundreds of them =D.

 

[TheHoove]

So my scrubber is going on two months. Im getting mostly yellow slimy growth with patches of brown. Except at the slot I get hair algae, and below the lights, bright green film covering the screen, with no dimension to it. I started at 10x14 screen, lit 10x10. I cut it down to7x14 lit 7x10. 23w actual CFL watts each side in 10" reflectors painted bright white. Flow is a little over 35GPH per inch, measured. Tank is 75g with about 15g sump/fuge. After i cleaned the screen tonight, I moved the lights back a bit, since i seem to get better green growth outside the light area. I have some patches of hair algae in the fuge under the scrubber. But very little display tank algae, maybe 2 1" spots of recurring hair algae, And some bubble algae here and there. But nothing bad. I feed 1 cube a day, and 1.5 every other day or so. So dont know If i need more light or less? Or maybe Just already low nutrients in my tank? I dont have an accurate phosphate test yet, and nitrates show 0 on a API test.

 

[JohnnyB in SD]

srusso has a good troubleshooting post #1902.
Since your flow is measured & known to be correct, your issue may be too much light. As you say, the more desirable algae is growing outside the central light zone. Moving the lights back some was probably a good move.
1 cube per day isn't very much food. A scrubber your size can handle a whole lot more, unless you don't have the livestock to consume it. One of the best things about an ATS is you don't have to starve your fish to maintain high water quality.

 

[Floyd R Turbo]

TheHoove, your problem is likely linked to low nutrients/light available for the scrubber to grow.

How close were the lights to begin with? How far did you move them back?

How does your tank look? Are your water parameters in line?

If everything is in good shape (the 2 ?'s above) then it's not really that much of a concern. Yes green algae filters better and there are benefits to having it, so you want to strive for it, over time.

If your water parameters are in line, try feeding one cube daily for a few weeks and watch parameters.

I just think the screen is starved, and under-lit. 2 x 23W = 46W on 70 sq in so it's about 2/3 strength, but still should handle 4 cubes of food a day, you're feeding 1/6 to 1/8 of that. I would consider feeding more or trimming the screen down again, in that order. Possibly adding iron (chelated)

JohnnyB, even if you don't have the livestock to consume uneaten food, it will decompose and the scrubber will take care of it...

 

[bad santa]

For the people that post on here to help us newbs out, do you think it would be possible to post the summary post #'s in your sig? I think it would make it easier for new people looking for the basic answers to find those posts.
I'm off to Wally world to find my screen and start my ATS today.

Thank you guys for all your valuable knowledge.

Basics summary on posts 2001-2010

good troubleshooting post #1902

 

[Floyd R Turbo]

RC doesn't allow you to put links in your signature, even if those links point to RC thread.

 

[rysher]

yellow growth usually means too much light, the algae is burnt.
try the "new sizing method", cut the lights in half, instead of 18hrs, try 9hrs for a few days and see what happens.
i'm a strong advocate of the new sizing method since i have tried it and now have green algae all over my screen instead of the patches of green here and there and mostly yellow on the middle.

 

[Floyd R Turbo]

Updated the threads on other sites with this, so just for consistency:

New Scrubber Sizing Guideline (Sept 2011)

Scrubbers will now be sized according to feeding. Nutrients "in" (feeding) must equal nutrients "out" (scrubber growth), no matter how many gallons you have. So...

An example VERTICAL waterfall screen size is 3 X 4 inches = 12 square inches of screen (7.5 X 10 cm = 75 sq cm) with a total of 12 real watts (not equivalent) of fluorescent light for 18 hours a day. If all 12 watts are on one side, it is a 1-sided screen. If 6 watts are on each side, it is a 2-sided screen, but the total is still 12 watts for 18 hours a day. This screen size and wattage should be able to handle the following amounts of daily feeding:

1 frozen cube per day (2-sided screen)
1/2 frozen cube per day (1-sided screen)
10 pinches of flake food per day (2-sided screen)
5 pinches of flake food per day (1-sided screen)
10 square inches (50 sq cm) of nori per day (2-sided screen)
5 square inches (50 sq cm) of nori per day (1-sided screen)
0.1 dry ounce (2.8 grams) of pellet food per day (2-sided screen)
0.05 dry ounce (1.4 grams) of pellet food per day (1-sided screen)

High-wattage technique: Double the wattage, and cut the hours in half (to 9 per day). This will get brown screens to grow green much faster. Thus the example above would be 12 watts on each side, for a total of 24 watts, but for only 9 hours per day. If growth starts to turn YELLOW, then increase the flow, or add iron, or reduce the number of hours. And since the bulbs are operating for 9 hours instead of 18, they will last 6 months instead of 3 months.

HORIZONTAL screens: Multiply the screen size by 4, and the wattage by 1.5

Flow is 24 hours, and is at least 35 gph per inch of width of screen [60 lph per cm], EVEN IF one sided or horizontal.

Very rough screen made of roughed-up-like-a-cactus plastic canvas.

Clean algae off of screen every 7 to 14 days, so that you can see the white screen material.

 

[TheHoove]

TheHoove, your problem is likely linked to low nutrients/light available for the scrubber to grow.

How close were the lights to begin with? How far did you move them back?

How does your tank look? Are your water parameters in line?

If everything is in good shape (the 2 ?'s above) then it's not really that much of a concern. Yes green algae filters better and there are benefits to having it, so you want to strive for it, over time.

If your water parameters are in line, try feeding one cube daily for a few weeks and watch parameters.

I just think the screen is starved, and under-lit. 2 x 23W = 46W on 70 sq in so it's about 2/3 strength, but still should handle 4 cubes of food a day, you're feeding 1/6 to 1/8 of that. I would consider feeding more or trimming the screen down again, in that order. Possibly adding iron (chelated)

JohnnyB, even if you don't have the livestock to consume uneaten food, it will decompose and the scrubber will take care of it...

Im kinda leaning towards low nutrients. Right now my tank looks great, but does have 2 smal spots of hair algae the grows super slow, and some bubble algae here and there. Its a 75, with 2 small clowns, 3" diamond goby, 2" Algae blenny, and 3" Kole tang. Plus CUC and corals.
The lights were about 4inches, moved them back to about 5" Angled away from the slow a little more.
I am working into feeding more to the corals.
I know the screen is under lit. ITs hard to fit more bulbs over that size screen, and 40+w bulbs are $10 each, the 23w ones are 12 for $24 at my local home depot. I dont want to go smaller on my screen as its overflow feed, already has more than 35gph per inch, and I dont want to slow down flow through my sump.

 

[Floyd R Turbo]

You want MORE intense light, not less. Moving the lights back is not going to make it better, it's going to make it worse.

If you have yellow algae, that means too much light compared to the nutrients delivered to it. The new 'black algae' lighting guidelines apply here. Move your lights back to 4" away and cut the photoperiod down by 6 hours so you're 12 on, 12 off, and let that grow for a week. You may need to adjust the time up or down until you find your 'sweet spot'.

You can leave your screen the same size and just consider it 'effectively' a 40/46 gallon scrubber or a 3-4 cube a day scrubber, or you could trim a little off the bottom. An oversize screen doesn't really matter though as long as the flow is right, the effectively illuminated area is all that really matters anyways. So leave the screen alone.

But your yellow algae is probably because there's not enough input into the system compared to the light the algae is receiving. The answer is to give the algae only the light it needs to perform the filtering it needs to do, or else it will start to go yellow. The photoperiod is just something you will have to play with, increase if you get brown to black algae, decrease if you get yellow algae. Make slow changes, say 1 hour change per week adjustment. Remember that you will go longer than before between changing lamps, and when you get to 3 months of usage you will need to start increasing the photoperiod so that you don't get yellow growth, and when you hit 18 hours a day, change 'em.

 

[bad santa]

What are you guys doing to hang/suspend your ATS? I need to figure that out today then my ATS will online

 

[srusso]

What are you guys doing to hang/suspend your ATS? I need to figure that out today then my ATS will online

Here is a great simple hanger I use... Not my idea but its a very good cheap one...

Take any PVC fitting, a 90 elbow, or a 45, a T... and cut the end that slips over the PVC pipe. You will be left with rings that perfectly slide over the PVC pipe. Cut a notch into each ring, effectively making it a "C" shape. You done. Slide the newly made "C" rings over the PVC, and twist into place... :celeb1:

 

[srusso]

For the people that post on here to help us newbs out, do you think it would be possible to post the summary post #'s in your sig? I think it would make it easier for new people looking for the basic answers to find those posts.
I'm off to Wally world to find my screen and start my ATS today.

Thank you guys for all your valuable knowledge.

Basics summary on posts 2001-2010

good troubleshooting post #1902

Good idea, much easier!

 

[srusso]

I'm still on my first week of an ATS setup i threw together in a couple of hours (including buying the parts) and i would say there is no way this will be more maintenance than the rest of the things going on with the tank anyway. Between twice daily feedings, daily sock changes, weekly skimmer cup cleaning and dosing/testing of various things; a once weekly clean with some brush seems hardly like a big deal.

I don't know if my flow is enough, as its still a very temporary solution, and my lights are sort of hacked into place, but its now 5 days in and the screen has growth on it, small brownish stuff, but growth none the less.

One issue i do have, even though the screen is in my sump, is i have snails (strombus maculatus) feeding on it... Not much hope in controlling them either, there are literally hundreds of them =D.

Them feeding on it may not be a bad thing... :spin2: it would make for a good experiment, 100% closed system?.... you have my brain working.... Thanks for posting this information.

 

[Gorgok]

Just cleaned my first week's gunk off the screen. Had to relocate 5 snails that hitched the ride out of the tank via the screen. Too bad for them they are now in an entirely separate system and no more screen munchies provided.... Took front and back pics of it for input.

Stat:
6.75" wide, 10.5" long. Roughly sized for 2 cubes a day.
2x 13W 2700K lights on both sides, with reflectors.
15 hours of light, inverse of main lights, but willing to tweak if necessary.
Flow unknown; it looks right and is provided by a Maxi-Jet Utility 1800 (474 gph rating) which at half rating is 35 gph per inch.