I know this is a highly debated topic but my curiosity has been aroused and now I'm in search of an answer. I have my 92 corner with a 400W, 20k MH pendant over the tank. It gets good light but now I'm wondering if it's enough. SPS, LPS, mushrooms, and softies don't seem to have any issues but when I begin to add hard corals...they don't do so well. Nor do clams. Am I missing the boat on the watts/gallon or is my spectrum missing something? I've not built my canopy yet and now would be the time to decide how much or what is needed. I have the equipment to add another 400 watts of MH or I can go with 130 watts to 260 watts of added PC's. Any thoughts would be appreciated.