my full grown oscars get fed once a day [nutrafin floating pellets] and only what they can eat within the first 3min about two to three pinches anythig more than that imo is a waste. An oscar might eat a 1/4 of the food you give him the rest gets spit out or passes through the gills and causes you more work and money in the long run
p.s. there is a pet store out here with a pacu and it must be about 3-4 ft long and about 2 feet high imo I would stay away from this fish
ill talk to you later 
