Answer by blacksmith37 for Can too much light kill fish?

No. I have seen a salt tank with coral ( and fish ) with 2000 + watts over a 150 gal tank. The big ones were metal halide but he also had other types of lights. There was a salt water club meeting at his house ; it was easy to find as there was bright light coming out the house window. As @ trond hansen points out , refrigeration is required to keep water cool with this level of light.