have a pacu in a 55g with a gold gourami and a cory catfish, hes a pretty decent sized fellah, workin on a new home for him in a larger tank. anyway hes never bothered anything in the tank until today. at one point I had about 15 small wild caught crayfish in there and it slowly whittled down to 2 of the largest ones, about 3'' each. i figured the larger ones had killed the smaller ones and eaten them- id seen each of the big guys with one in their grasp before eatn away, but that was alot to eat for 2 crayfish. one of them poked out of his rock today and sort up swam up into the water real fast when the catfish swam by, and the pacu caught sight of him and nipped at him, ripped a claw off, and then completely destroyed him, ate every last morsel, i didnt know they were that carnivorous? maybe hes the reason all the crayfish are gone?