I have been wondering the same about more than one flasher. I have been told its a crap shoot even if the colors aren't similar so I have been hesitant. I do know rhough that flashers will be fine with other wrasses as I currently have a mckoskers in with a six line, melaneraus, and a eecently added lunar. All have been togerher for about six months and not one agression issue. Added note my flasher was first added and all other added at sperate time so I didn't put to much stress on the most peaceful (flasher). Good luck and please update on situation...