small size tank top ATS for fresh water

[Keithp]

Floyd,

I chose to use a solid material because it can be 1 sided. If I keep the water on the lit side only, It should need less flow for the same width of screen. This should keep the efficiency up. I have nothing against canvas except that there is no way to prevent water from going to the unlit side without a lot of silicone. I feel that reflecors are not 100% effective, especially these DIY pots that don't have ideal curvature so it may be better to wrap the growing medium around a single standard lamp with more direct light.

Thanks for your input.

[Floyd R Turbo]

I see where your thinking has brought you, but if the screen is held in place by surface tension, and all the algae grows on one side, because that's where the light is coming from, I think it would still work. You might consider using some material to act as a clip like what this guy used

http://algaescrubber.net/forums/show...light=adhesion

and bond that along the top edge of the box then slide the screen into it. This would force the water to flow over the top of the clip and over to the lit side of the screen.

[kotlec]

That is interesting topic about single sided screen . I agree with Keithp that flow will be divided somewhat, but not expect to be big part. On the other hand will this underneath flow helps roots of algae to feed and not to dye longer ? That would be a plus. I am myself on the crossroad to cover acryl plate with plastic canvas or not . Hope Santa will clear that for us.

[Rumpy Pumpy]

Nice design.

Squeezes a lot of screen width into a small area and very efficient use of the light source.

Considered something similar a while back but with a circular chamber instead of square and a single piece rounded canvas screen, but couldn't figure out a way to hold the canvas in place reliably and still make it easy to remove for cleaning.


By the way, if you wanted to go with plastic canvas rather than solid screens a good way for you to hang them would be to use plastic channel like this



Silicone the screen into one channel and use the other to hang it on the edges of the chamber.

[Keithp]

I see where your thinking has brought you, but if the screen is held in place by surface tension, and all the algae grows on one side, because that's where the light is coming from, I think it would still work. You might consider using some material to act as a clip like what this guy used

http://algaescrubber.net/forums/show...light=adhesion

and bond that along the top edge of the box then slide the screen into it. This would force the water to flow over the top of the clip and over to the lit side of the screen.

If you look at my original attempt with the nut jar, I actually tacked on a screen. Part of the reason I gave up was because the water had a greater tendency to spray off the canvas. I probably could have fixed it but the nut jar was so small and hard to work with that I gave up instead. I just thought I would try it without the screen first on the acrylic version because it is easier. The cement board does not seem to have trouble growing algae and I didn't have to rough it up. Once the screen has fully established I may swap out one or more of the panels with an alternate screen or material just for fun.

The only reasons I think the screen may be better than the cement board is if they have undesirable chemicals or if the fact that they are screens encourages more transfer with the air and additional turbulence with possibly some slow pockets that might help attach algae. After thinking it through, I don't think the additional air exposure is all that important. I don't know what to think about turbulence and slow pockets other than I am happy to have less splashing. The cement board manufacturer specs didn't look to be a problem but I am not much of a chemist and you never know what might be added or naturally in the material. Just think of the children's toys from china with large concentrations of lead, mercury and cadmium going into their little mouths. The plastic screens and cement boards both have potential for bad substances. If I am wrong, please let me know.

[Keithp]

That is interesting topic about single sided screen . I agree with Keithp that flow will be divided somewhat, but not expect to be big part. On the other hand will this underneath flow helps roots of algae to feed and not to dye longer ? That would be a plus. I am myself on the crossroad to cover acryl plate with plastic canvas or not . Hope Santa will clear that for us.

I think algae likes growing on rock and concrete better than on plastic but base that on minimal experience and hearsay rather than scientific proof. If true, rubbing on a little wet cement to some of those vertical screens might even improve algae growth. Of course it may be because the rocks and concrete leach some phosphate like Santa Monica warned. Part of the beauty of this design is that the material can be interchanged easily but it would take more work to set up a screen than a simple board of whatever material. Also since I built it with clear acrylic a screen mounted directly to the clear acrylic would be too bright in the room. If you do something similar, use black acrylic, plan on covering it or be willing to live with additional room lighting.

I didn't think algae had roots like most terrestrial plants. I read what looks like a root is really more of a way to tie to a surface rather than nutrient uptake. Not sure where I read it though. If I am correct the material doesn't matter much as long as the algae sticks to it and it doesn't poison the water. PETE in food and drink containers is not very good for this based on my experience with the nut jar.

Having lights on both sides may help light the algae strands near the "root" which might make them stronger so I may end up needing to clean the screen more often to avoid strands falling off. I won't know until mine is more established. The whole point of my design is to limit power consumption so I only use one light, and a small pump only capable of lifting a few feet instead of from a sump. My Maxijet pump uses 10 watts vs. the biowheel filter at 14.4 watts and it would be a lot more if I had to use a pump in a sump. If using LEDs which are one sided, this design wouldn't make as much sense except that you can always find a replacement bulb quickly.

If I had a sump and a very large tank needing the scrubbing power of multiple lights, I would have built a more typical scrubber screen with tube lights and reflectors.

Good luck with yours.

[Keithp]

Nice design.

Squeezes a lot of screen width into a small area and very efficient use of the light source.

Considered something similar a while back but with a circular chamber instead of square and a single piece rounded canvas screen, but couldn't figure out a way to hold the canvas in place reliably and still make it easy to remove for cleaning.


By the way, if you wanted to go with plastic canvas rather than solid screens a good way for you to hang them would be to use plastic channel like this



Silicone the screen into one channel and use the other to hang it on the edges of the chamber.

Rumpy,

About a week ago, I read the thread where you were considering the curved one but I wasn't sure how you were going to make it work. I was going to try and find that thread again to see if you had any success so I am glad you mentioned it. Circular would have an even better efficiency but it seemed more expensive and difficult to construct. Still I am sure someone will figure out how to make it happen eventually. The inside face of my cement board is 5"x5"x7" tall so even a small CFL is less than 3" from the farthest corner. The bottom panel is also covered with cement board and seems to be growing at a similar rate to the side panels.

If the cement board works well enough I probably won't try the screen because of the splashing and it is unnecessary work. I suspect my pump is not pushing enough water to grow as effectively on a screen where some of the water flows behind. Also there isn't much adventure in it since everyone knows it works. If you or anyone else can think of another material that you would like to see in action, I would be happy to insert it on one of the sides for however long it takes. Having an extra screen would mean I could feed the pleco with one while it is not in the scrubber.

[jnad]

Hello!
I see that you are using sement bord as an alternative to plastic canvas.

Have you seen this scenen material, i think it is great for single sided screen:
http://algaescrubber.net/forums/show...highlight=Jnad

Jnad

[Keithp]

Hello!
I see that you are using sement bord as an alternative to plastic canvas.

Have you seen this scenen material, i think it is great for single sided screen:
http://algaescrubber.net/forums/show...highlight=Jnad

Jnad

That material looks like it works pretty well. Did you ever get thicker growth? I tried to find the material on line but Google failed me. I wonder if your tank just didn't have spores for the hair algae. I kept tanks for years with no hair but once it starts, you are stuck with it. At least it isn't growing in your display either.

I have extra travertine and slate which I might try. I had heard slate is safe in tanks and I would like to try it. I keep the boxes in the crawl space and am not looking forward to crawling through spiders to get it.

I chose to go 4 sided to keep the board close to the light and because I think even really good reflectors are only adding 90% more light to 1 side. Even most professional reflectors are not shaped to reflect the most light possible. With my design, I catch 4 sides plus the bottom with direct light. My lid also has a mirror but probably has little value and I only added it because it was in the acrylic discount box.

Like you, I get some condensation on the lid but the light is warm enough that it is mostly limited to the trough areas so algae should not be much of a concern. I want to cover the bulb with glass or acrylic instead of sealing it with silicone to make it safer and easier to change but I also don't want to have to clean the cover. I am waiting to see how thick the algae gets and to see if there will be any spray before putting anything together.

Thanks for your link and for sharing your ideas.

[jnad]

Hello!
I almost got these Steni screens growing green in an other scrubber project i did.
Here is the scrubber: http://algaescrubber.net/forums/show...+algaescrubber

I do think these Steni plates is very good screen material in singel sided scrubbers. If i should make an single sided scrubber i would use the Steni plates again.

Jnad