Originally posted by DSkidmore
With the bulbs, spectrum and bulb life are the critical factors. the Kelvin rating is the highest peak in the spectrum, not the only one. Look for bulbs with multiple spectrum peaks on that light color chart. Also look for bulbs that last longer.
This is solid info, but to add to it, the amount of PAR (Photosynthetically Active Radiation) is another key factor in bulb selection. Basically, the more PAR a bulb emits, the more energy is available for corals and their zooxanthellae to use.
Hobbyists just need to be careful in how PAR is distributed. Too much can actually be harmful to corals. Corals such as SPS require more PAR than say mushrooms or polyps.
Originally posted by Bang Guy
Do a web search on "Dana Riddle". he has done extensive research on many aquarium bulbs & ballasts.
Also, Joe Burger and Sanjay Joshi are two others who have done extensive on reef lighting. Joe has done some great work providing stats on 250W MH bulbs, and Sanjay has just done a ton of research with MH lighting.