i came across a good deal on a metal halide light fixture for my 55gal planted 500w you think it would be toooooo much also looking at a 250w T5 fixture, but for the price the MH fixture is a much better deal...
what do you all think?

I don't know much about lighting, but the $300 plus clamp on halides are sweet for planted tanks. The point light source makes really cool patterns in the tank as it passes through the agitated surface. I'm definately getting some when I have extra $$$.

I've seen the clamp on type on a 20 gallon and there was no algae problem and the plants were doing great. It was at the aquarium store.