i built a led lt for my 90, 2 48in x 6in heat sinks welded together, 36 cree xpg cool white, 27 xpe royal blue ,9 xpe blue, 6 eln-60-48d drivers, diy sunset/sunrise simulator, no optics, lt @ 1 in above tank, glass canopy, tank 48x16x24high, driving the whites @ 1300ma and the blues @ 900ma, the penetration is good, the distribution is good, and it shimmers, it is definately brighter than my Current USA 4xt5 ho 4ft fixture, i am lps dominant with some sps, all are doing well. you definately should use the cree xpg and xpe leds, i got mine from cutter electronics in australia, got free shipping and $30 COD for taxes & brokerage (before HST), got my drivers from rapidled and they do sell xpg but i don't think xpe. i am new to this forum and not sure how to send pictures. all my leds are bin 5. this link has a few pictures, it is post #34
http://www.reefcentral.com/forums/sh...r#post17418032