Lighting Rule?

[lionfish]

LionFish says.....
Well, I need a little help from someone who knows how much light there should be for a reef tank to mantain corals. I'm setting up a 50 gallon in 2 weeks so I want to know how much light I will need. I've heard numerous answers to this question before but don't really have a clear answer. I can have as much wattage as a want so tell me what kind of lighting will be able to support clams.

 

[mr . salty]

Clams require the most light,around 5 watts per gallon.The general rule is 3-5 watts per gallon. But many believe that placement is more important than total watts.

 

[lionfish]

LionFish says.....
Well, I went out and bought a JBJ power compact with four 96 watt bulbs. Came with dawn/dusk control too. Not cheap though. I am planning on putting in a Maxima clam. I found that book and it is very interesting. Well, I figured I would need about 400 watts so I got 374 watts of power here. You guys think that will be enough for the clams?