Ok at the Pet Supplies Plus in my town there is a nice 5-6 inch red belly piranha for (get ready for this) $8!!!!! I want it so badly but it's a little bigger than the ones I have right now, I would of had it in my tank already buuuut the people there told me that it was dropped off by some guy who just couldn't keep it anymore cause it was too big for his tank. This piranha was kept alone all of it's life in its former owner's care. I'm worried that this guy won't take to being in a shoal well due to being alone all of its life and will beat up my shoal. I know that you can't predict if a fish will adapt to being in a shoal, is there a big risk in adding this new fish since it has been alone in a tank without tankmates?