How high should a 400w MH be?

[FishGeek]

beacuse you are running only one light in the middle, you have to worry about the pread of the light. If you mount it too close, the light wont cover very much of your tank. I say mount it highter so the light spread covers more of your tank. Don't forget that you have a shallow tank and 400w metal halides are good for tanks 36" deep so i don't think you have to worry about how close to the tank surface you mount that sucker!!!! Just my opinion.

Oh yah, did you get a clam already?

Simon