I dont like the look of torn fins,so mine are all by them selves,also when they are kept together the less dominant fish will not show its best head/color
If the FH is still small (under 5") You can maybe add a group of 3 Tinfoil Barbs but make sure that they are bigger then your FH and a large pleco. I'm keeping my ZZ BD who is only about 4" with (2) 6.5" Tinfoil Barbs and a 11" Commom Pleco but thats in a 120....If your FH is over 6" and is already very aggressive then a pleco would be your best best because i doubt anything else will survive unless you have a large tank.