How much LED's Needed for my tank?

[jarmitage]

Hey guys,

Is there anyone who could offer me some advice as to how many leds would be required to light my tank. I want to grow some easy corals , mushrooms, xenia , frogspawn etc. I am thinking of buying this kit from rapid led.

http://www.rapidled.com/servlet/the-53/24-Ultra-Premium-LED/Detail

my dimensions are . In centimeters , 74cm long, 46cm width, 50cm deep.
inches : 29.13 long, 18.11 width, 16.69 deep.

44.97 gallons, or 170 litres ( if you live over in my part of the world :) )

:bounce3: Cheers guys :bounce2:

[jimnrose]

I'm using 72 LED's for my 72" x 24" x 16" and running them at about 2 watts/led. I have a 50/50 mix of white and royal blue for about 6 months.
So I would say 24 would be fine & 30 would be better for more light diffusion.
I found there is no need for lenses. Running 6 led's per driver thereby gives you either 4 or 5 circuits. 30 LE's would allow one row (running the leds lengthwise) is great for morning/evening, then 2 rows for mid day and 2 rows for high intenswity. I run 3 circuits off a 24hr timer. The morning/evening are at 3/4w; mid day at 1 3/4w & high intensity at 2 1/4W each. Yuou can change the intensity (power) via the current driver.
Using aluminum U channel (extrusion) for the heat sinks [3cm x 3 cm] is less expensive and allows better placement of the leds; instead of traditional heat sinks. LOL, Jim

[jarmitage]

Hey Jim, Thanks for the reply, it was very helpful. I think I will try and make my own heatsinks, the U channel aluminum sounds like a great idea, I have a friend that has a workshop full of stuff for drilling/making threads etc. I think I will go with the 24led kit, and if i need more light, or a more diffuse light i will supplement with a couple of T5's. I want to make a sleek hood, but power is also a concern so LEDs are going to very helpful.
I dont know if my electronic skills are good enough to set up potentiometers ( is that the right word? ) and multiple clever cat circuits. Think i will just go a for a straight circuit + 24hr timer on this one.