I've got 11 chromis in my tank right now. According to urban legend, they should have started cannibalizing each other months ago. Strange that since I started feeding them non-stop I haven't lost any... Chromis are like sharks... always swimming, eating...I don't think I ever want a chromis or multiples in a tank again, lol. I have no doubt there is 0% chance any new chromis would last a day. Not worth this risk of adding something that has a greater likelihood of carrying uronema than doesnt.
I think playing the waiting game is what I'd opt for. I've seen even tiny wrasses go after much larger fish when they get seriously ticked off.

