I've posted a few times in a few forums with no response so I'm assuming that I'm the only one to ever try this fish combination. Tomorrow, unless I'm advised otherwise, I'm adding my two pajama cardinals to my 75 gallon, which has a school of seven glass cardinals in it. The pajamas don't bother anything in their current tank (firefish, sleeper goby, coral beauty, shrimp) so hopefully they won't bother the smaller cardinals. I know sometimes mixing the same species is risky, but they really look nothing alike and maybe that will be the deciding factor.