I have a seven inch Gulf spiney turtle with fish,I think its a male because it has a lot of spots and a nice olive green color. I read that the females have a darker brown shell while the males keep there color when they get full grown and stay half the size of females,so far he does not bother any of my fish,they are all large fish some over 26 inches the smallest about 5 they are in a 420 gallon tank,so if I have a male I do not think it would be a problem.So what do you think?