Algae Scrubber Basics

[scolley]

can you post a diagram of what happens without optics?

Sure, XR-Es at the same distance, same configuration, no optics...

Clearly more overlap. But I'm going to go back and play with a pattern that spaces the two rows out more, and uses tighter optics for less overlap. Both the 80 degree, and no optics, appear to have too much light on some spots - particularly the center - areas. Going to have to play. But it all comes down to whether my current light spot in the center of my screen is due to too much light, or the abuse I gave it this weekend. Should know in a few days. If it's not filled in soon... the problem is likely the light.

Without the optics, you would get better overall coverage being so close to the screen, but you would want a diamond diffuser plate so blend it all together.

Yes. Good suggestion. Thanks. IF I decide to go without optics, and since it has become clear that I've got to incorporate splash screens, this could work well for both. Thanks!

 

[bucks448]

That makes a lot of sense Bucks. Just due to the reduced flow fewer nutrients would be available right? The other side of me says that a long slow flow may export the nutrients more completely out of the water though? So while I move less water across the screen I am pulling a higher percentage out each pass?
Just a thought.
For the record I decided to go with a 10x13 canvas.

The lighting point is great though, why waste the resources.

Slower flow allows more contact time and removes more nutrients is counterintuitive for a scrubber. If you think about it, the water isn't pooling like in a refuge. It's cascading, so even at lower GPH it's moving pretty quickly over the screen. With slower flow you end up with uneven coverage. Also, water will take the path of least resistance, so as the screen fills in you'll end up with dead spots. I think it's been said before...you can't have too much flow, unless it's pulling the algae off the screen.

Also, check out Floyd's summary posts 1035 and 1036.

 

[Floyd R Turbo]

If you have 35-50 GPH/in, you'll rarely get channeling on a vertical screen, as long as your slot tube is cut straight. If algae tries to grow into the slot tube, the pressure increases and prevents further growth. As far as channeling lower on the screen, it's unlikely to happen in the long run because as the water finds a better path, that path gets more flow and fills in. It's like a self-correcting control system. Horizontal screens are where you get the bad channeling.

The taller, narrower screen can definitely be done, vertical space is really the limiting factor here. Most people don't have 24" tall to run a scrubber and mount lights.

The taller screen would in essence filter exactly the same, except that as the screen grew in and algae strands got longer, they would build up thicker towards the bottom of the screen and block more and more light further down. However, I think you would have to have it taller than 24" to start realizing this loss factor. If you started to encounter issues, you just may have to shorten your cleaning period to 5 or 6 days instead of 7.

 

[Floyd R Turbo]

Scrubber update

Scrubber update

Well it took me a week but I finally got the scrubber up and running again. It's totally ghetto and super loud without an enclosure or lid for the scrubber box, but it's running and the screens are no longer hanging loose in the tank!

Besides the noise, I have lots of bubbles. There always has been with this scrubber, but they never made it into the DT from the sump because they were big enough and they just rose to the surface.

The light isn't blocked extremely well so it makes for a very bright moonlight effect in the tank, which is actually pretty cool. But I should probably fix this.

The frame itself is sitting on the back edge of the rim, because I thought it was a bad idea to set it on the center brace. It's a good thing I decided to set the tank stand 3" off the wall. The frame is also held in place by the DT light fixture, but it's not depending on it for support, just a little bump in position (to keep it slightly more vertical).

I"m running it from a Mag5 which is sunk in that little basket, which is made of 1/2" PVC pipe for a 'frame' and the #7 mesh and zip-ties for a particle filter. Lucky for me, I had 2 Mag5's laying around, because in the process of building the basket, I dropped one and shattered the ceramic impeller rod. Oops.

So like I said, totally ghetto but totally functional. The one thing I should have done was include a shutoff valve after the pump, because then I would be able to dial back the flow so that it isn't so loud. The noise is because of the way I designed the drains. Like I've said before, I've learned a lot from Rev1 and Rev2. Rev3 will be killer. But there might be Rev2.5 coming soon for this temp setup.

 

[Psyops]

Mr. Turbo,

Would you use a filter sock for the return or does that reduce the nutrients for the scrubber? I have a scrubber that is about 45 degree angle. I just tipped a horizontal one. I will one day do a vertical one because I have a 36 inch high base, but I want to do my system one thing at a time. Also spend more time learning the specifics of a vertical system. my present system is 240 square inches.

Thanks
Alex

 

[Floyd R Turbo]

Uneaten food and fish waste is organic N and P. Bacteria consume and convert this to inorganic N and P, and this is what test kits test for. This is also what algae consumes. So trapping fish waste and uneaten food really does not hinder scrubber growth, as algae does not consume this form of N and P. There's plenty of it in the system that isn't trapped by the filter sock.

A filter sock will trap pods. Any that are large enough and free-floating and find their way to the sock will get trapped.

That is really the extent of the effect of running filter socks on a system with a scrubber.

 

[Lwhite]

Ok so I got this built today, it is 7x13 for a 40B with a 15g sump. Lit by two 23W 2700k bulbs with 8" reflectors. I am moving approximately 260 gph across the screen.

Before I sit and wait and hope for the best does anyone see any problems with this design/ setup or anything that I should fix?

Thanks!
-Luke

Note that while you cannot see how rough the screen is, i took a saw blade to it for a 2 hour movie so it is pretty well mangled

 

[Floyd R Turbo]

I would center both lights on the vertical center of the screen and point them directly at it (no angle). Your screen is oversized but all you care about is the effective area. Light both sides equally on one section.

Also are you overflow or pump feeding? What's the tube on the near side?

 

[Arusso713]

I was just at homedepot and saw some 40 watt meds lights that screw in a normal light socket for 29 dollars 2700k

 

[Lwhite]

Will do with moving the lights, I am overflow feeding. The tube on the near side is an overflow safety, Even though I had cut a nice straight line that was exactly to size for the screen, I got a lot of side spray and back pressure, I just put a drain line on the end to relieve the excess pressure. Is that a bad thing? I am still getting a nice smooth waterfall off the screen with full coverage and no channeling.

Edit: I am using a beananimal overflow off of a side drilled tank, so you can see the three downtubes in the back. I just took the full siphon tube that can be flow controlled and turned it into rigid pvc tubing feeding the ATS. I have just capped off the end of the flex tubing after the ats, so there is only a small amount of pressure bleeding through it, but it is enough to keep the water from spraying everywhere. This actually forced significantly more water over the screen, so that is probably a good thing


Here is a new pic with the cap on the end of the flex line, and the lamps moved. Looking better?

 

[Psyops]

thanks Turbo for the response. I have noticed pods in my sock.

 

[Travis1787]

Lwhite to me that light on the right looks to high and I don't see anything protect the drain line so ya might get blockage from algae in the slit of the pipe also lots of light is wasted over the pipe on that same side id try and get in more in line with the light on the left

 

[Travis1787]

that one on the right also looks rather close both side should both be the same distance away I believe ... 3 or 4 inches from the screen

 

[Floyd R Turbo]

Yes, 3-4 inches from the screen and centered on the vertical center of the screen. The right light is too high. If you're running a Beananimal 3-pipe then you have no need for the emergency overflow, it will just allow the slot to clog because as algae grows into it, the water will have another path to follow and you will get reduced to no flow. Allowing the head pressure to build above the slot tube will prevent algae from growing into the slot tube. Like a self-adjusting control system. I would cap the end of the pipe and install a spray blocker.

 

[pskelton]

Progress with my algae scrubber but some questions

I started a 55 gallon tank last September with a deep sand bed and a cheap but heavily modified protean skimmer. In November my wonderful Niece spent a week with us and early one morning before we woke up she decided to dump a full container of food into my tank and for whatever reason she dump sugar in the tank as well. My frog spawn was mortally wounded during this event but everything else survived (mostly Zoanthids and other soft corals. Fish did not care). In February I had a snowflake eel given to me and he immediately started burrowing in my sand bed. This released a lot of nutrients and after about a month my nitrate spiked to 160. For several weeks of water changes the nitrate was not dropping, it always came back up to 160.
I had been reading about algae scrubbers and though I would give it a try. On the 3rd screen cleaning my nitrates were down to 60. I have seen a substantial drop every week since the implementation of the ATS. This week (4th screen cleaning) nitrate is still at 60 and my rocks are starting to grow GHA.
I am guessing that the new GHA growth on the rocks is due to junk leaching out of them. With nitrate stuck at 60 for the last two weeks I believe that the nitrate in the water has now dropped below what is stuck in the rocks. As the ATS pulls nitrate out of the water the rocks and sand are leaching back into the water column. At least that’s what I think is happening.
I was wondering if this theory is consistent with what other have experienced? Does anyone have any guess how long it should take to get nitrate into a safe range?
Should I consider vodka dosing for a while?
Should I be concerned about my deep sand bed? Could I have a ticking time bomb on my hands due to excess nutrients trapped?
Any advice is appreciated

 

[srusso]

Sure, XR-Es at the same distance, same configuration, no optics...

Clearly more overlap. But I'm going to go back and play with a pattern that spaces the two rows out more, and uses tighter optics for less overlap. Both the 80 degree, and no optics, appear to have too much light on some spots - particularly the center - areas. Going to have to play. But it all comes down to whether my current light spot in the center of my screen is due to too much light, or the abuse I gave it this weekend. Should know in a few days. If it's not filled in soon... the problem is likely the light.

Yes. Good suggestion. Thanks. IF I decide to go without optics, and since it has become clear that I've got to incorporate splash screens, this could work well for both. Thanks!

The answer seems so simple then, scrap the optics and use less LEDs.... No?

 

[srusso]

I would center both lights on the vertical center of the screen and point them directly at it (no angle). Your screen is oversized but all you care about is the effective area. Light both sides equally on one section.

Also are you overflow or pump feeding? What's the tube on the near side?

+1, center lights

 

[srusso]

Progress with my algae scrubber but some questions

I started a 55 gallon tank last September with a deep sand bed and a cheap but heavily modified protean skimmer. In November my wonderful Niece spent a week with us and early one morning before we woke up she decided to dump a full container of food into my tank and for whatever reason she dump sugar in the tank as well. My frog spawn was mortally wounded during this event but everything else survived (mostly Zoanthids and other soft corals. Fish did not care). In February I had a snowflake eel given to me and he immediately started burrowing in my sand bed. This released a lot of nutrients and after about a month my nitrate spiked to 160. For several weeks of water changes the nitrate was not dropping, it always came back up to 160.
I had been reading about algae scrubbers and though I would give it a try. On the 3rd screen cleaning my nitrates were down to 60. I have seen a substantial drop every week since the implementation of the ATS. This week (4th screen cleaning) nitrate is still at 60 and my rocks are starting to grow GHA.
I am guessing that the new GHA growth on the rocks is due to junk leaching out of them. With nitrate stuck at 60 for the last two weeks I believe that the nitrate in the water has now dropped below what is stuck in the rocks. As the ATS pulls nitrate out of the water the rocks and sand are leaching back into the water column. At least that's what I think is happening.
I was wondering if this theory is consistent with what other have experienced? Does anyone have any guess how long it should take to get nitrate into a safe range?
Should I consider vodka dosing for a while?
Should I be concerned about my deep sand bed? Could I have a ticking time bomb on my hands due to excess nutrients trapped?
Any advice is appreciated

Rock leaching will only show in the form of algae growing on the rocks, not shown in the water column, however I guess anything is possible... but I believe its your BSD that is creating any nitrates at this point.

Generally you want slow, small moves when it comes to a BSD... that being said some snails, some star fish and other burrowing creatures are what you want... Adding the snowflake eel was a bit like putting an elephant in your tank... Not to mention the amount of waste an eel can create is not helping you in this case either...

I don't remember what your scrubber setup is, but you should ensure that its running perfectly so fight this battle! That being said, I don't think it will be long before the scrubber removes everything from the water column.

Keep up with water changes
I don't like the idea of vodka dosing any tank... so I wouldn't do it. I will let someone else speak on that subject.

 

[Floyd R Turbo]

Vodka dosing, IIRC, is a form of carbon dosing. Carbon dosing has been shown to reduce algae screen growth.

 

[BigRick]

Does anyone sell good algae scrubbers or are the only DIY?