The males will out grow the females 5 to 1. Find yourself 2 or 3 shells roughly 5-6 inches long with an opening large enough for your smallest fish to go into, and spread them around the tank. it won't be long before you know what's what. They will eat about anything, and get along with about everything. The one exception is two competing males. I had 2 that tolerated each other, but at a different time I had 2 that fought until one was dead. Small Compressiceps will have a hard time surviving around some more aggressive fish, even their own size. Once they get larger they can hold their own.
