Can you tell me what you dont like about yours? maybe I can avoid the same problem...
Sure ... I made so it wouldn't extend forward of the glass lids or rear of the filters. Each end still extends the full width of the tanks so it's not only supported by the glass tops. This kept it narrow, light, fit a narrow 4' 2-bulb shop light, and initially worked out fine on the tank I had it on. Now it's on a 150 and the glass tops don't sit 100% flat, so it's pitched in the center. It also barely fits between the hinges on the lids and the Emperor 400s hanging on the back.
In retrospect I wish I would have made it like a traditional canopy and had it cover the entire top of the tank, with enough of a hinged opening in the front to easily open the glass tops, and high enough that it just sits over the filters. It'd be heavier, but it'd look better and be easier to line up when putting it back on.
