How many Cree LEDs do I need...

[cmholl]

I'm looking at buying a driver and a few LEDs. Was looking at 8 cool whites and 2 royal blues from rapidled.com. I was wondering if this would be enough LEDs for a 37 gallon column tank. I believe the tank is 20x18x24(lxwxh). Was just wanting to know if the Cree LEDs will be enough light to add a shimmer?

 

[2quills]

Shimmer wouldn't be a problem. Are you looking to supliment another light source that you're already using or is this going to be your primary light source?
8 white and 2 blue is going to produce a predominantly white look.

 

[acrylic51]

Tagging along.....What are you keeping in the tank as well.......

 

[acrylic51]

Now for:
FO tanks. (Fish Only)
Area/20 = number of LEDs
Soft Coral tanks
Area/18 = number of LEDs
For SPS tanks
Area/16 = number of LEDs.
Now this RofThumb also expects:
No optics
LEDs within about 4 inches of the surface
XPG whites
XTE RB
All LEDs driven at around 700mA.

 

[cmholl]

ITagging along.....What are you keeping in the tank as well.......
[/quote
It would be used for fish only tank. The tank I have is 20x18x24. I would be putting 40degree lenses on each led. So I would take the surface area divided by 20 which would give me 18 LEDs needed?