I remember reading somewhere (but I cant remember where) that it was a good idea to keep an aquarium level. It suggested putting cardboard under the stand so it can kind of adjust itself to be flat. Since I cant remember where I read this to look it up does anyone have any opinions on this? Will it put unnecessary stress on the tank or was it just because a crooked water line looks ugly? I just moved to a new place and after setting my tank back up, a week later as the water started dropping its not quite even. The water is at the bottom of the rim on one side and about 1/4th an inch from it on another.