I am contemplating adding (at the request of my wife) a Blue Hippo Tang to my tank. I currently have a 55g long tank with (in addition to a slew of invertebrates) a Fire Goby and 2 Clarkiis, one about 2" and the other about 3". The last time I tried to add a fish to my system I only had a 30 gal. I added a bi-colored Angel and the next morning it was dead. Now I didn't actually see him being bullied but I have seen the Clarkiis bully the Goby (couldn't catch him) and a Royal Gramma (fought back after about a minute). Any thoughts? Would I be better off with a smaller Tang or a larger one?