My gold mysery snail has escaped 2 times in a row. Thankfully he didn't damage his shell too badly. The first time he fell onto the table the tank is on, however last night he landed on the tile (a good 4ft drop). I've always had plastic craft mesh cut to fit the opening where the filter comes into the tank, but it's climbing out the outtake onto the filter and then falls from there. I even tried lowering the water level and that doesn't seem to help. Is there anything else I can try to put over the opening to keep it safe? If not, I'll have to try and move him to my son's frog tank which is the only one where there is no way to escape, but I'd hate to do that right now since my other snails don't seem to do well in that tank for some reason.