I have mine with an Oscar, and they get along just fine...however, at work, we have the baby ones housed with baby pitcus cats, and everybody seems happy. What exactly did you have in mind?
What size tank do you have, hun? That cute booger is going to get HUGE, probably close to three feet, just so you know!! He *shouldn't* pose a threat to other fish, as he would much prefer to have a piece of zucchini rather than a fish, but we have those customers who insist that their pacu loves feeder fish...probably because they are not offering anything else to the poor things.