I have a lion fish, lunar wrasse, 2 tomato clowns, dog face puffer, fox face rabbit fish, and a small snow flake eel in my 180. I had put 2 different tangs in there and they didnt live. I fear that while i never saw them getting messed with that may have been the cause of there stress. So my question is this. What is some more options that I can add to my tank?