thats common misconception. There arent any catfish that scavenge. They are all hunters and eat opportunisticly. You should do your best to feed all your catfish the proper food it requires for their diets. That being said. Your hybrid will be an eating machine. The other fish in the tank are future food. Im sure your cat is looking around and just contemplating the day it can have each of them as a snack.
You need to be feeding it shrimp, krill, bloodworms, beef heart, start now getting it on pelleted foods. Look up threads by necrocanis to see what you will need to be feeding it in the near future.