if you want a community of fish, then pick silver dollars. They look like piranhas, swim like piranhas, and shoal like piranhas. They don't hunt and kill tankmates like piranhas. Get rid of the RBPs and get some silver dollars.
Piranhas are funny because the people that want to keep them (other than the die hard fanatics who know what they're getting into) generally have this macho fish hang up about keeping fish with teeth, but then when they get them and they don't do anything exciting they wish that their vicious fish were able to be kept with others. It doesn't work that way,
They are what they are appreciate them as they are or keep something else.
Think about the quality of life for whatever you keep with them. I mean just about anything you keep with piranha is gonna suffer fin nips at the very least if not outright death. Normally when people talk about how successful a particular species is at being cohabited with piranhas is how much armor it has, or how fast it is. What kind of life is that for the tankmate always being vulnerable to predation, hiding and escaping death at every moment. Not a very nice way to keep the other fish.
Most piranha keepers know that there are generally only two kinds of fish in a piranha tank:
a) piranhas
b) feeders- some more expensive than others
Piranha tanks should be species only for every one involved unless we are talking about HUGE tanks.
just my opinion...
