It is one of the genus Leporinus, I am pretty sure it is the striped leporinus (Leporinus striatus) as that is the only one I have seen imported that has horizonyal stripes. If so it gets to 10" max and eats mainly algae and plants, it will pick at nori sheets, cucumber and squash slices, etc. and should recieve a food designed for vegetarians. It will also eat tropical flake food, small inverts, and tiny fish. They like a bit of current and tend to pick on smaller or timid fish, their own kind, and anything that looks like them.
They are south american but not picky about pH.
By the way, welcome to MFK.