What are you feeding your Pacu? Mine are on Hikari Cichlid Staple floating pellets, Bananas, grapes, carrots and mice (when they feel like it). I don't argue with them, they busted my 150 right in front of me, all over the floor couple years ago. I had a banana in my hand standing across from them in the kitchen and wasn't paying attention. They got it alright. About 100 gallons of that tank was on my floor in a split second. They both just rammed it in the corner at the same time. You can keep the bigger one's I'm trying to not force mine any bigger to fast. I bought them that 220 they are in and that better last them awhile.