Thanks for your help! Unfortunately that only breaks it down by tangs/surgeonfish in general not the sub-species of tangs. I know some tangs get along well other tangs (ie - some Zebrasoma may get along with some Acanthurus who may get along with some Ctenochaetus, etc) and some will fight. I am just wondering if anyone is keeping a Powder Blue and a Desjardini Sailfin Tang together peacefully? I have them in my tank already and they seem to be getting along well (other than the initial territorial fighting of course). I just didn't want to find out from a long list of people that this was a bad combination or I would have moved one to another one of my tanks.