Is that true? I was to spice up my boys, sell the two smallest of my six and add one more fish.(77G Tank) I heard caribe would mix in. I was think one that was 6-7", my 4 RB's that would be left would be 6" each. I know I'd have to take em all out, Re-ararnage the tank and re-introude. But I just want to make sure what Piranha you could put with RB's. Some Imput would be Apreciated, thanks. Go Canucks go!