I've got 4 9" RB in a 125 gal. at my house but I just started college and they won't let me bring a tank that big, are their any types of piranhas that would be alright in say a 15 or 20 gallon tank?
Two years max I hope. If that is the case get you a 20long and I think a small. S. Sanchezi, Brandtii or even like a 2" rhom would be good in there untill you move out.
I'm only going to be in here a year, well from now until mid-may. would a small altuve be alright or not? I've wanted one of those for a long time, but it wouldnt be able to have a big tank until i got home and set one up for it.