I bought an Aqueon 24" Deluxe Flourescent Full Hood today as well as a 20G tall tank that measures 24" long and 12" wide from the outside of the glass. The hood measures at 23" long and just under 12" wide. This causes the hood to bend in and not sit on the tank at all. Am I supposed to use this in conjunction with a glass lid? Does anyone have a quick fix for the time being or am I using this wrong in some way?