Algae Scrubber Basics

[Floyd R Turbo]

I'll stick around as long as they let me. I intend to stay and not cross their lines because I simply believe in helping others realize the simplicity and effectiveness of this system. It's not for everyone, but that doesn't bother me. I'm fine with being a subset.

 

[rysher]

that's why i stopped responding to posts about scrubbers.


on another note, i am happy to inform you guys that i have solved my cyano/red slime problem in my fuge. i redid my ATS box using a black acrylic box, no more light goes in the sump. red slime is gone.

 

[dogstar74]

Srusso, and Floyd, Don't say good-bye yet. The mods don't ban you unless the tenor of your posts is inflammatory. So step away from the threads for a while and let them cool down. It'd not wise to bring issues from one thread to light in another thread. It only gets them both closed. Let that sleeping dog lie.

Hey if anyone's interested, My small ATS built for my 10 gallon is working, but not at full capacity. I have twice the screen size that I need. But the problem I've run into is burning of the algae on the screens. I'm getting good green growth at the bottoms of the screens (the farthest from the lights) and it's yellow thin and burnt in the middles. I attribute this to the lights being too close.

My next itteration will be to take out the center bulb, remove one of the screens and place the other one in the center. This should position the screen further from the lights to avoid burning, and will still be plenty for my size of tank.

I'll report back after the changes have been made.

Cheers, and chin up guys. Just bring down the tenor a bit and keep plugging on.

Aaron

 

[inky]

Def a big thanks to Floyd and Srusso

 

[jeremy-40]

In need of help!!!!!

In need of help!!!!!

Ok so my scrubber has now been set up for about 12 weeks now and all I get is a yellow spongy type of growth. I have never got any green growth on it at all. The yellow stuff gets about 1/8 to 1/4 inch thick in the 7 day period but never any hair algae. I have tried several different things like cutting back the time my light is on, moving the light further away from the screen, iron supplementing, and different flow rates. I am getting so frustrated with this thing and now don't know what to do. My tank is covered in hair algae and I just don't see it receding at all.

Scrubber details:
Display tank is 20 long
Screen is single sided, 7" across 10" down
Light is a 26w CFL, now approx. 5.5" away from the screen
Lights are now currently set for 16 on 6 off
Scrubber is plumbed off of my return from the display
Pump is way overpowered for my tank and I have more than enough flow
Nitrate and phosphate all test 0 on my test kits

Is it possible to have too much flow????? That's the only thing I haven't realty throttled back. Attached are a few picture of my setup. I really dont know what i am doing wrong. Please help!!!!

 

[srusso]

Move the light closer to around 3" - 4" away, besure your using a 2700k bulb. You can't really over due the flow unless you start to see algae falling from the screen because of the strong flow. Hold off on dosing any more iron at the moment. Get the lighting back to 18 hours on 6 off. Clean algae from your screen as much as possible every 3 - 4 days, until you get green growth. To give the screen a kick start if your ok with it, go dark in your display for a day or two...

Report back after the third cleaning. From the pictures though it seems you have the flow right, I wouldn't mess with it... Just besure your getting at least 35gph per inch of width.

 

[TheFishMan65]

I will restrict my posts to the proper building and design of an algae scrubber.

So where should I go for instrucions on cleaning . (That's humor by the way, for anyone without a wierd bone.) Thanks for keeping this on topic as I slowly drift off to one side.

 

[TheFishMan65]

Oops missed a page.

srusso, I had the same problem with a URL in a signature. I don't remember if I got PMed. Relax if you try to follow the rules you will be fine - just don't ignore warnings. They probably just did a blanket clean of the signature rather than trying to figure out what was OK (time issues).

I am glad you (srusso) are still here. Turbo not going to help with trouble shooting either

 

[Floyd R Turbo]

My tank is covered in hair algae and I just don't see it receding at all.

Scrubber details:
Display tank is 20 long
Screen is single sided, 7" across 10" down
Light is a 26w CFL, now approx. 5.5" away from the screen
Lights are now currently set for 16 on 6 off
Scrubber is plumbed off of my return from the display
Pump is way overpowered for my tank and I have more than enough flow
Nitrate and phosphate all test 0 on my test kits

Is it possible to have too much flow????? That's the only thing I haven't realty throttled back. Attached are a few picture of my setup. I really dont know what i am doing wrong. Please help!!!!

If your tank is covered in GHA and your N and P are zero, I would say that right now you have an effective algae scrubber - in your tank. There may be phosphates in the rockwork that will need to be leeched out, depending on how long the P has been 0. The GHA on the DT rocks will persist until this supply dwindles.

What I would do is try to harvest all the algae you can from the display and throw it away (your screen is 'started' so you won't benefit from smearing it on the screen, it will just wash away), and black out your tank for a few days. In this case, you need to force the algae to have a preference about where to grow. Once it get a strong foothold on the screen, then it will take over.

Like srusso said, move your light closer, make sure it's 2700-3500K, and do light cleanings, once a week should be fine. Try not to clean it too much, just use your fingertips (not nails) and if you have any long strands of GHA on the screen, try not to scrape them off, rather you could break them and leave about 1-2" hanging on the screen (a scissors might help). You can clean any GHA off that is at the bottom or top 2", so that applies to the center area of the screen really.

Are you running any other filtration besides live rock? N and P at zero could be a limiting factor, again your DT algae could be eating these up.

 

[Floyd R Turbo]

So where should I go for instrucions on cleaning . (That's humor by the way, for anyone without a wierd bone.) Thanks for keeping this on topic as I slowly drift off to one side.

I should have added troubleshooting to the list of things I can comment on.

Also I will comment regarding other filtration systems used on conjunction with an algae scrubber, as I have before, but really only to the extent of the effect that they have on an algae scrubber. So I won't give advice to remove one piece of equipment or another, and voice my opinion about the usefulness or effectiveness of another filtration system.

 

[Enjoy]

I'm not sure if it has been asked (probably has, so forgive me) - Is it possible to have to large of a scrubber?

I have a 50g frag tank that I planned to run a 10" x 10" screen lit on both sides. Will this be too large for this system?

TIA

 

[Floyd R Turbo]

It depends on how much light you put on it. If you build one 10x10 and then put 50W of light on it, you'll have a double-sized half capacity filter.

I can really see no downside to an oversized screen, other than the fact that you will have that much more area to clean each week, and if you light it with 1W/sq in then you'll use more energy.

The primary factors that affect filtration capacity are light, flow, and size. Assuming that flow is always 35 GPH/in or width, if you have a screen that is 2x the tank size and the lighting is the same as the tank size, you may get a small percentage of additional filtration. If you have screen and lighting matched (double the tank) then the screen just may not grow as thick and full as it would if you match the screen and light to the tank size, just because the algae can only absorb what you throw at it. At least that is what logically makes sense to me.

As far as a rationale for doubling the size of the screen & lighting, there are a few instances where it may be a good idea. Off the top of my head would be things like if you had a really, really huge bio-load, or wanted the extra filtration capacity to act as a cushion (for instance, in case of a fish dying in the middle of your LR structure causing an ammonia increase), or if you feed a ton of food, or if you drip liquid coral food on a continuous basis. The latter really pushes an algae scrubber to the limit from what I've read, so you would want a powerful scrubber and you would have to monitor your water pretty close and adjust your feeding amounts as necessary.

 

[srusso]

I'm not sure if it has been asked (probably has, so forgive me) - Is it possible to have to large of a scrubber?

I have a 50g frag tank that I planned to run a 10" x 10" screen lit on both sides. Will this be too large for this system?

TIA

This is something I have tried on my own tank and I have been now for 8 months.

One thing to keep in mind is that if you decide to make an over-sized scrubber all other parts need to be properly sized for that size scrubber.

Seems simple enough but, I like many others before me, tried to squeeze a little more from my lighting and a little more from my pump and ended up coming up short.

The problems your scrubber will have, will not show for quite some time... And for the most part you have working scrubber, even though its now both starved of light and flow... I can say after 8 months that I am forced to redesign my scrubber.

I will be cutting the screen down to be properly sized for my 70 gallon, cutting a new slot tube, and moving my lighting to accommodate the new screen size. These are my first hand findings... they may not be yours... Additionally an oversized scrubber will take longer to fully mature...

I will say though, I believe (this is my own opinion) algae scrubber sizes in relation to tank sizes are very, VERY modest... IMHO a scrubber built for 100 gallon tank could run, a normally stocked 150 gallon. Reason being, I don't think you could feed heavily enough and stock enough fish/corals into a 100 gallon without other issues arising... tank mate aggression, chemical warfare between corals, etc.... does that make sense?

I have no hard evidence to prove this, just a feeling I have based on my own findings.

 

[Floyd R Turbo]

I will say though, I believe (this is my own opinion) algae scrubber sizes in relation to tank sizes are very, VERY modest... IMHO a scrubber built for 100 gallon tank could run, a normally stocked 150 gallon. Reason being, I don't think you could feed heavily enough and stock enough fish/corals into a 100 gallon without other issues arising... tank mate aggression, chemical warfare between corals, etc.... does that make sense?

I have no hard evidence to prove this, just a feeling I have based on my own findings.

Many others have reported similar efficiency so this is about right. The only thing I would add is that for a 100g size scrubber to handle a normally stocked 150, it must be well designed and able to handle a full bio-load of a 100 gallon tank. If you build a scrubber and it is lacking in design in one area which detracts from it's effectiveness and then you push it by putting it on a larger system than it is designed for, you may or may not encounter problems with N or P down the road. It would just be something to keep an eye on. Like I always say, know the limitations of your scrubber.

A well designed scrubber will handle a tank that most would consider "fully stocked" with corals and fish. A larger, lighter stocked tank would be handled by the same scrubber. A smaller, overstocked tank would also. The correlation is just pretty much what makes logical sense.

The scrubber that I had running on the 125 acrylic tank that cracked was technically undersized (and still is) because I am running 4 x 24W T5HO on a 20" x 7" screen, and it was at about 60% flow for the first 6 months, on what considered a fully stocked tank (not quite overstocked, but that is debatable). The flipside is that I used TEK-II reflectors and a workhorse ballast, so I was getting all you can get from those lamps, plus I would get the 3D growth which is supposed to contribute to growth and scrubbing power. That tank also had 250+ LB LR.

 

[jeremy-40]

Move the light closer to around 3" - 4" away, besure your using a 2700k bulb. You can't really over due the flow unless you start to see algae falling from the screen because of the strong flow. Hold off on dosing any more iron at the moment. Get the lighting back to 18 hours on 6 off. Clean algae from your screen as much as possible every 3 - 4 days, until you get green growth. To give the screen a kick start if your ok with it, go dark in your display for a day or two...

Report back after the third cleaning. From the pictures though it seems you have the flow right, I wouldn't mess with it... Just besure your getting at least 35gph per inch of width.

If your tank is covered in GHA and your N and P are zero, I would say that right now you have an effective algae scrubber - in your tank. There may be phosphates in the rockwork that will need to be leeched out, depending on how long the P has been 0. The GHA on the DT rocks will persist until this supply dwindles.

What I would do is try to harvest all the algae you can from the display and throw it away (your screen is 'started' so you won't benefit from smearing it on the screen, it will just wash away), and black out your tank for a few days. In this case, you need to force the algae to have a preference about where to grow. Once it get a strong foothold on the screen, then it will take over.

Like srusso said, move your light closer, make sure it's 2700-3500K, and do light cleanings, once a week should be fine. Try not to clean it too much, just use your fingertips (not nails) and if you have any long strands of GHA on the screen, try not to scrape them off, rather you could break them and leave about 1-2" hanging on the screen (a scissors might help). You can clean any GHA off that is at the bottom or top 2", so that applies to the center area of the screen really.

Are you running any other filtration besides live rock? N and P at zero could be a limiting factor, again your DT algae could be eating these up.

My light is 2700k and for the first 2 months it was 3-4 inches from the screen, but since it never greened up for me I was thinking it was burning the algae so I backed the light off and I still get the same growth. I have also been covering the display for three days a week for the past 3weeks and this did not help either. I will stop the iron dosing and try cleaning the screen more often (with finger tips only)and see where that takes me. I also do not have any other filtration on this tank. Thanks for you help.

 

[Floyd R Turbo]

I would think that within the first month you should have had some level of green growth. How bad if your DT algae? Have you ever harvested any of it?

As far as the iron dosing goes, I missed that one. The only time I ever dosed iron was after I discovered that I had a lot lower flow than I needed (like 60% of what I needed) and I thought my growth was hindered by that. You would already need a somewhat mature screen for iron dosing to help IMO. Whatever you are adding is likely causing the DT algae to grow faster.

Stop the iron dosing and harvest the DT algae every couple of days or so for the next couple weeks. Also consider that GHA loves high flow, so if you have a lot of flow for the size tank, that will also contribute to algae growth. Even with the scrubber, my powerheads grow GHA well because they are up high by the light and in high flow. I just cleaned one that was so bad that it wasn't even moving water! If you have a ton of flow in your tank, that could be a piece of the puzzle also. I'm not saying to cut it back, just looking for possible root causes.

 

[jeremy-40]

I would think that within the first month you should have had some level of green growth. How bad if your DT algae? Have you ever harvested any of it?

As far as the iron dosing goes, I missed that one. The only time I ever dosed iron was after I discovered that I had a lot lower flow than I needed (like 60% of what I needed) and I thought my growth was hindered by that. You would already need a somewhat mature screen for iron dosing to help IMO. Whatever you are adding is likely causing the DT algae to grow faster.

Stop the iron dosing and harvest the DT algae every couple of days or so for the next couple weeks. Also consider that GHA loves high flow, so if you have a lot of flow for the size tank, that will also contribute to algae growth. Even with the scrubber, my powerheads grow GHA well because they are up high by the light and in high flow. I just cleaned one that was so bad that it wasn't even moving water! If you have a ton of flow in your tank, that could be a piece of the puzzle also. I'm not saying to cut it back, just looking for possible root causes.

I set the tank up just a few weeks before the scrubber and used old live rock I had in my refugium for my 100 gallon tank (probably has been in the fuge for 2 or more years). At the time they did not have any algae on them but with in a few weeks they were covered, this is why I set up the scrubber. I dosed the iron due to the yellow color of the algae on my screen and now that u say it I was probably just feeding the algae in the display, so I will stop dosing completely. I have harvested a little at a time but will now do it on a regular basis. I do have a lot of flow in the display, because my return pump is a little too big for this tank, but is doing it's job and I don't want to have to buy a new one. I will definitely give all your (and srusso's) tips a try and I really appreaciate the advice.

I WILL BEAT THIS ALGAE!!!!!!:hammer:

 

[pskelton]

My screen is going into week 4 and nitrates are dropping fast. Please see attached pic I am concerned about the circles. is this burning from too much light or something else.
Thanks

 

[srusso]

My screen is going into week 4 and nitrates are dropping fast. Please see attached pic I am concerned about the circles. is this burning from too much light or something else.
Thanks

These types of circuls come from copepods, not burning. Be sure your rinsing your screen under tap during each cleaning. The fresh water kills the copepods, this step is very important that needs to be done every week.

 

[pskelton]

I have been washing it with tap water during my weekly cleanings. Do you think that I should clean it more than once a week for a while?