Know you what else works? Don't buy males. Females have very little webbing between their toes, males have a lot of webbing. We have both together, and one guy is very annoying to everyone else in the tank. We have lots of hiding places, and actually, they are not stupid - we yell at the troublemaker and open the lid, so we can separate him from his victim, and now he understands that if the yelling starts, he'll be unceremoniously pulled off and put in an isolation cell for a few minutes, so he lets go and hides in the plants when he hears yelling and sees us coming.