Originally Posted by Daemonfly
I have a 55w AHSupply kit over my 20g long. The way it's mounted, it's about ~4"-" from the water surface. If I were to do it over, I'd make it higher, due to light spread. It's designed to be fully "openable" so thats not a factor.
What do you mean by light spread, are you having problems with it spreading front to back, or on the sides? I don't think i'll have a problem getting light to the sides with the 55 and the 13 watt kits, but I hadn't even thought about front to back.