Is there such thing as too much lighting???

[ScubaSteve]

There is, however, a maximum amount of light that corals can use. This level is called the saturation point, beyond which you start to get photoinhibition. I had the same question a while ago.

Look at Advanced Aquarist Magazine online; they have a lot of articles on this topic, particularly with respect to different algae clades. As stated above, too much light too fast = bad and lots of light can be good for growth, but there is a point where you start to get decreasing returns on the amount of energy you're pumping into the tank.