I can only relate my own experience, but here is what I have found to be successful. I bought a hatchling florida softshell and kept it for four years. When I finally ran out of room for it, it was 18 inches long and was getting too big for the 120 gallon tank I had it in. Originally, as a hatchling it was kept in a 20 gallon long aquarium, with a sand substrate, a weathered, smooth log for a basking area, water temps of approx 78 degrees and a basking spot in the upper 80's. Food was reptomin sticks, earthworms and small feeder fish. The same conditions were replicated in it's next 3 tanks, a 40 gallon, 75 gallon and lastly a 120 gallon. The only thing with the larger tanks I didn't use was sand. Too much of a hastle to keep clean. I was running two fluval 403's on the 120 gallon and doing large water changes weekly. Food was the same, pellets, large feeder fish, earthworms with the occasional pinky thrown in. She had a real personality, stood up on her hind legs in the tank looking for food. It was cute to see. I loved her to death but I just didn't have the room for a 400 gallon stock tank(which is what she needed) so I gave her to a friend who had one in his basement family room.(wives that will tolerate that are hard to find). Just remember, they're cute now, but if it's a female of any of the species they get very large, very quickly when maintained properly. If you don't have the space to house an adult you shouldn't get one. I was lucky that I had a friend who would take her.