Pacu is mostly a herbivore. And comically enough they do like to eat nuts that fall out of trees, that's what they use those flat teeth on.
Somebody bought it when it was an inch long and of course the pet shop owner didn't tell him it would soon grow larger that the buyers aquarium. When they are babies they look very much like red belly pirahna.
Not onlike many of the plecos I see being sold in stores. Most people don't know they're going to get a foot long.
