My turtles love to swim. As much exercise as they get swimming I can't imagine that they will ever be over weight. They are the size of a quarter and have 50 some odd gallons and a waterfall to play in. I keep it just low enough so that they can't get out. When they aren't basking they are swimming and playing in the waterfall. At first the current surprised them, but now they love it. All the set-ups I have seen the water is half full or even less. Why? Thanks, Julene



