They are 2 36 watt bulbs 1 10k daylight and one true actinic. I swapped mine out and put in 2 50/50's I like the way the color now spreads evenly throughout the tank. But you can keep alot of things, colt coral leathers, xenia, hammer corals, plate corals (stick to the short tenticles IMO). Shrooms, zoa's... the list goes on.