best place and best bulb I've ever seen/used is the 10k XM. Pat has them at ReefLife. They're expensive bulbs though.. You'll also need actinic supplement, as they're WHITE.
The best I've heard of but not used is the ReefLux 10k, which are supposed to be white with a blue sheen. Expensive if you can find them locally (I believe), but online they're the same price as the XMs online.