I use 8 LED with a dimmer, there blue and sit at 470nm this is the wavelength that moonlight is @ aprox 10-20 feet under the water. looks great, they turn on just befor 03's go off and stay on till 0400. I used a kit from this guy
www.thelebos.com/index_moonlight.html
all you need to make it I did a twist on the mounting part and put them in LED holders from Radio Shack and put them in a great plastic channal used for running house hold wiring on the outside of walls fron Home Depot. If anybody wants more info or pics just PM me Ill e-mail them to you.
this is the cannel I used
www.wiremold.com look for cordmate II
P.S. my tank even looks beter than the pics at lebos imo
Richard