it really does depend on the individual fish, my 1.5" RBP is much meaner than the two bigger RBPs that he shoals with, he is always the first one to the kill, and eats the most. Hes also the brave one too, always first to go check out anything new and then eat it.
ive seen finger chaser brantii,elongs,rhoms,sanchezi,geryii,caribe,altuvie, gibbus......... pretty much them all ive also even seen some mean *** finger chasing reds
There is no aggresive piranha species. They are all potentially equally aggressive. It just depends on the fish itsef and the habitat in which it lives.