It might create dead spots and a place for the crud to build up.I made a stand out of plastic waste pipe for legs and grid lock from payless plastics so it is hollow under the rocks to stop traping waste.I put a spay bar under there and the the tank has never looked better and has been very stable.You also need less rock.Down the front the rock still sits on the glass but i have had rock on glass for the last 9 years with no problems.