Questions! I've got a terrapin and it seems to be doing ok so far since i got him months ago, but still want to ask a couple questions. Firstly, how often should you clean their tank? Secondly, do they need huge tank? (mine's only a baby...kinda....7-10cm) last, do they need a lot of water in the tank or just a tiny bit? i know they swim and stuff, but i heard from a mate that if they're kept in a tank full of water all the time, their shells can soften, which can be fatal?