[QUOTE]
Originally posted by orbit
depending on the kind of light ( MH or T5), a full canopy will create alot of heat, u can install fans to cool it off,
as for a glass cover, i heard it was bad for the tank,i kinda forgot the reason why, maybe some one here knows y [/QUOTE
I agree alot of air exchange occurs at the surface of the tank--this area should be kept really turbulent by power heads etc.--I would remove the glass
I have a wooden canopy over my light fixture below--it has been a real limiting factor for lighting due to heat issues. I can only run 150 halides and have had to cut two 4 inch holes in the top and install fans to dissipate the heat.