I currently have a 55g long tank set up with 3 mudskippers, mollies and swordtails(in brackish water of course) the tank is about a 1/3rd full for the fish, i just switched from gravel to sand and am trying to find an easy was of making a sandy beach without having half the tank built up with sand so that he fish will still have the room that i would like them to have. I was thinking of getting a glass piece cut with a slight lip and siliconing it to the tank, then filling it with sand, altho i am uncertain as to whther this will be a good idea as sand can be quite heavy. Anyone have any ideas???