agreed. red bellied pacu. They need an extremely large tank due to their potential size. Ive seen them kept in HUGE tanks with giant pink bellied gouramis and tinfoil barbs.
200 gallons is pushing it. Really they belong in at least 500 gallons, an indoor pond is a great idea. If you look around on Monster Fish Keepers, they have lots of threads with rbp's in big ole' indoor ponds. They get 3 ft!
Yeah, the whole 200+ thing was meaning that the absolute minimum is 200 gallons (from what I read online on various sites)...as with all monster fish, the bigger, the better.