CichlidFish.com - Fish That Think.

well ive got two red belly pacus. I had one a couple years ago, and i jsut got two new ones. The only thing im wondering is when i put a worm in their for my oscar the pacus eat them. I thought they were vegitarians?

Yeah, a lot of people believe that.  hah!  They do eat a lot of vegetable matter in their native habitat, but they aren't vegetarians.  They also phenomenal eating machines, and they get HUGE! 

A Pacu can out-eat an Oscar any day of the week. They grow fast and become huge -- you'll need over 200 gallon aquarium for them two Pacus. They will become the size of a large dinner plate, and they startle very easily. They've been known to break the glass in a smaller aquarium when startled, and they dash away -- BOOM -- right into the glass. Usually, they are not aggressive, however, so you can keep small species with them. But make sure you have A LOT of aquarium for these monsters!

I was at an aquarium this summer and they had Pacu's that were 5 and 6 feet long. I couldn't believe it.