I have never had a problem with my blue legs going after my snails. But the red legs are less agressive. I would stay away from the turbo snails. They fall off the rocks and land on the bottom, upside down and can't flip over and dye. You need to get crabs in your tank. They are great fun to watch. Very busy little guys. Always working, and add a lot to the look of the tank when people come over and look inside.