well the only piranha species available in my is RBP
I used to have a school of them in a 100 g tank previously,
Now my 100 g tank is full with bichirs, but I still have an empty 50 g at home which I thought I could used it for a solo fish. I saw a 9" RBP being sold in my lfs and I was thinking of having it in my tank.It seems that the bigger they are the less skitties they'd become. But I dunno about this, and its still within my plan.