Size for nano LED scrubber

[RkClimber]

First off I'd like to say I've been reading your articles on algae scrubbers and I really like the information I'm hearing. I've been out of the hobby for about 15 years now after closing down a build & maintenance aquarium services I used to have. I'm going to be starting an 18g nano reef, the last reef that I had was an 8g in a 10g tank with just a skinner & mechanical filtration 25 years ago. The dimensions of the new tank are, 16"W x 16"L x 18"T. I was planning on using an old powerhead that's rated at 265 gph. The Scrubber I plan to build will be 7.5" W & 3" Tall, using LEDs that's going to be mounted above the tank inside the canopy, in this way the pods can drop right into the tank. So is this to small? I'm basing the size off of your articles, 35 gph per in. then going with the tallest size I can get in the canopy I'm going to build. Aesthetics is what's keeping the canopy to a low height. Regarding the leds what kelvin rating would you suggest 3500 or 6500K? Tanks so much for your contribution to this hobby.

[kerry]

Hello, you will need to read the new sizing info here: http://algaescrubber.net/forums/showthread.php?1419-New-sizing-guidelines . As far as the LED's go, it looks like the research suggests using the 660nm 3watt LED's. These are working for myself and others here.

[RkClimber]

Ok, so if my screen is 7"W x 2"H with 6watts on each side running 35gph through each linear inch of the 7" I could feed 1 cube per day. I'm assuming 1 cube is way more than is needed for an 18 gallon reef tank with a few fish in it. But being that the screen is only 2 inches high is that going to be a problem, or no since I've got my 12 square inches and I've got my 6 watts per side I'm fine? If I'm using LEDs do I still want 6 watts of LEDs on each side that would be two 3W LEDs on each side or since they get so much more light do I need to reduce the amount of watts? One more thing which I did ask in another post which you're so kind me to help answer is how far away do I want to keep my LEDs from the screen originally I was thinking .5" but now I'm afraid of burning the algae but I want to keep the Scrubber very narrow?

[kerry]

I used two LEDs per side because I wanted to have plenty of light and coverage and maybe run them on a shorter on cycle. With your length I think you will need two per side to get light coverage on the screen. I think .5" would be to close and burn the algae.

[RkClimber]

Ok, now even if I'm running them on a shorter cycle u think that's (.5") too close? The closest you would do would be what 1.5" or quick cycle 1"? I'm designing this in a CAD program & having a laser cut the parts for me, so I can get really accurate with this thing. I want to do it right the first time that's why I'm asking so many questions.

[kerry]

I had to increase my flow just a bit because I was burning my algae at 1.5" so i would say .5" is way to close. I think 1.5" is good as you can always and a LED if needed as that is easier then a redesign.

[RkClimber]

Ok, got it, tanks you so much for the help. Back to the computer to redesign. I love working in my CAD program. :)