Need help! Making a nano(pico) sized LED scrubber singleside

[Gigaah]

So I got myself into the whole Pico reef frenzy. I'm planning on building a 1.5g Pico(10Lx6x6). due to aesthetics I'm going to have to go with a single sided screen. I do plan on hanging the screen as you with if you were going to light both sides vertical..but I will only be lighting one side(I think that should be ok/possibly better than just having the screen laying backed up to something). Pico's being very tiny habitats..I really want the scrubber to be quite oversized to help keep the parameters stable. Also the aesthetics are only having to add 2x6x10 on to the back of the unit for the filtation will also look really good as most pico's have a big ugly black box on the side that is a 4-6".

I have an aqueon pump that is *rated at 200GPH. its off an aqueon HOB quiet flow 30. I'm currently planning on making the screen 5x5(the growth portion will be 5x4). If you translate that into a regular double sided screen you'd be looking at 6.6sq sq inches per gallon. So that should be powerful enough I think.

I've never done a single sided scrubber. and I plan on using some 1W warm white LED's to light it(the good star mounted type). I'm really at a roadblock on how many I'll need. They will sit about 2" from the screen(that could be increased to 3 if I HAD to). I'm not sure if they will be burning in the algae or if i might need to "frost" the acrylic between the LED's and the screen. Anyone with LED single sided scrubber experience could really help me out.

I'm really excited to get this project rolling. I think the nano/pico community could really reap a benefit from algae scrubbers. I know most of them have to do quite frequent large water changes. My GOAL is to have ZERO water changes like I do on my 30 and 55gallon. In my dream of dreams...I'd like to get such a healthy pico it could handle a dragonet like a baby mandarin or scooter bleny..tho I know they may out grow the tank size wise in the end. I know I'll hear a lot of "it can't be done"..it wont be happy..it'll die..etc. But I've heard all that before as I happily housed 4(two mated pairs) of mandarin(spotted/green) in one 55 gallon scrubbed tank along with a scooter bleny. all fat and happy each one of them.

Any input on the light and sizing would be VERY appreciated.

[Ace25]

I would go with 660nm Red LEDs from Rapidled.com. Warm whites will work, but reds will work much better IMO. Since your tank is so small your going to need to most efficient ATS setup you can possibly make.

http://www.rapidled.com/servlet/the-172 ... Red/Detail (http://www.rapidled.com/servlet/the-172/Osram-660nm-3W-Red/Detail)

If you go that route, I would go with the Meanwell 700mA constant current driver and go with 3 LEDs. Reason I pick 3 is I believe the driver requires at least 3 LEDs, and also those LEDs don't have any optics available for them (yet).

I will let others (Santa Monica) speak about the design of the scrubber since his advice is much better than mine in that regard.

As far as the tank, 1.5G, I think your biggest obstacle will be salinity/evaporation, which is easy to solve ahead of time with some type of auto top off setup.

[Gigaah]

I had already determined evaporation would be an issue. So my design will be sealed to prevent it. I also was thinking of puttting a very small bottle upside down in the scrubber area. So when the water level drops it will release fresh water. Sort of like those fancy dog water bowls that take a 2 litre bottle and keep the bowl full. Ill consider the reds. But I already have the warm whites on ahnd so I was hoping to use them. I have 10 of the 1w warm whites. If 10w isn't enough then I would consider red... but I feel 1w leds are probably a better choice. I also have the appropriate driverfor the ones I have on hand.

[Ace25]

Gotcha, I did exactly the same thing.. I went with what I had on hand at first, then added reds later on so I know how you feel.. so I say go for it. :D

Ya, the upside down water bottle trick is certainly an option for top offs.. it is very cheap and easy to try out, if it doesn't work your not really out anything but a little time.

[rygh]

That 10W on a 20 sq in screen is 0.5 W/in2.
My guess is that it is probably too powerful.

I have 30W on a 336 sq in screen, so 0.1 W/in2.
(That is per side, so matches your single sided)
Although I do have red/blue, which (at least I believe) is a fair bit more efficient than warm white.

My suggestion:
Build it as you plan.
But add maybe 2 layers of diamond diffusion grating. (At home depot, in lighting area)
It disperses the light well, and will actually cut it down a bit.
Then start out with less hours/day, and see how it goes.

[dtyharry]

I thought the recommended guideline was 1w per square inch and 1 square inch per gallon

[Gigaah]

I think due to the highly focused nature of LED's using the 1w per sq inch is too much from what I understand. using a single sided screen its recommended 2sq" per gallon..and I'm all about overkill and its soo tiny any how I just made a size that would fit nicely into the tank design. Not to mention nano's can use all the help they can get so over sized is a good idea.

Pictures of the current design I will post due to a request. Plans currently involve having the whole unit tightly sealed..and as long as I can pull it off the water will touch to lid so you can see clearly into the tank from above! I REALLY hope I can pull this one off it would look so nice.

If anyone has suggestions, comments or anything I'm more than willing to hear them out. I havn't cut any acyrlic just yet. But I have the pump, LED's, cooling fan/heatsink for the LED and acrylic on hand now.


BTW I love google sketchup..its fast and easy to make quick designs in.

[SantaMonica]

Maybe could get more LED's spread out more.

[Gigaah]

Thats not a bad idea. I was worried from a previous post by another experienced LED user that 9w was going to be too much. If I get more I could add red as some have suggested. I might be ordering some Ultra violet for "actinic" display lighting so adding some reds wouldn't be a big deal.

[rygh]

Looks like a pretty slick design.
Since the light is single sided, you probably want to make sure the majority of the water flow is on the side
with the lights, so anchor screen tightly to the side away from lights.
Hope that makes sense.

Designing big is good. Easy to make smaller if you change your mind.

BTW: The specifics on my setup:
I have about a 250 gallon tank.
I have two double sided 10"x13" screens, for a true surface area of 2 * 2 * 10 * 13 = 520 in2
That is the same as the 1 square inch per gallon in the faq.
I have 8 standard reds, 4 deep reds, 2 blues, and 12 warm whites, all at 700mA
That ends up being about 60W.
So for that, I am at 0.25 watts / gallon, instead of 1 watt/gallon.
Which since it is more efficient than CFL, makes sense.
That ends up being 0.11 watts / true square inch.

I get a lot of growth, zero N/P. However, I still have some algae in main tank, so mine is not perfect yet.

--

I really suggest royal blue, not true ultra violet LEDs. Almost as good for fluorescence, but safer.

[Gigaah]

Thanks for the specs on your light set up. That will give me a base line for what I'm doing.

Yes the part about anchoring the screen does make sense. in fact the overflow design was specifically made with this thought in mind. If The screen can't be to fight tightly against that back lip, then I'll move the lip the screen mounts to back towards the display a bit so the water has to flow over the one side only.

[Gigaah]

Well not quite "ultra" violet. More like violet. 405nm. Catch some of the volet range that you get from metal hailide lights that leds are lacking. True ultra violet leds are uber expensive anyhow.

[SantaMonica]

"True square inch" will probably confuse people. It's probably more productive to stick with Length X Width, 2-sided, = area.

In this case, you'd be at .22 watts per sq in. And if you double everything in order to get the extra power to clean your display, you'd be at .44 watts. Which is about the same as the minumum recommended .5 watts. Although 1.0 watts is better.