I have a 7" YBS and a 5" map turtle in a 50 gallon with goldfish and a pleco. I have put cichlids and other kinds of exotic fish of all kinds in with them, and they do fine. The turtle might try to chase them but then get bored and find something else to do. My turtles are fine with them (they've lived with fish all their lives), but it really depends. I recommend that whatever you get better be a fast fish!