Hello everyone. I've had my 20 gal. tank set up for about a year and a half now and have only one Banggai Cardinal. I thought about mating the fish but can't tell the sex and don't want to risk it. I'd like to get another fish in there and would like your advice on what to get. I've tried unsuccessfully to keep a Royal Gramma because the Banggai was way too aggressive and thought the Gramma would do alright. What fish, if any, could I keep successfully with the Banggai? I was thinking a mated pair of Oscellaris Clowns (no anemone) or something that could hold it's own (no damsels of course). I definitely don't want to overload my tank. What do you think? Thanks!