Pet shops sell channel catfish (Ictalurus punctatus) when they're tiny youngsters. Properly fed channel catfish, though, will grow to about 60 pounds. Channel catfish will grow large enough to require an outdoor pond or an aquarium with a capacity of several hundred gallons.
Staple Foods
Essentially, channel catfish like to eat everything. They are omnivores that lean toward meaty foods. They will eat just about anything they can fit in their mouths and will make a good try at anything else. For their day-to-day feedings, you can feed a flake or pellet food. Generally, you should use flake foods for young channel cats and pellets for larger fish. Many pet shops sell flakes and pellets specifically formulated for catfish. Use prepared foods like these as the main food for your fish.
Frozen Foods
Young channel catfish relish foods like bloodworms and brine shrimp. Many pet shops sell frozen cubes and blocks of these organisms. Break off a bit and toss it into the water. Be careful with bloodworms; many people are allergic to them. On a staple diet supplemented with bloodworms and brine shrimp, a young channel catfish can grow as much as an inch a month.
Live Food
Live food in the aquarium is a special treat for channel catfish. They respond well to live foods, apparently relishing the chance to hunt. Many pet shops sell food items like feeder guppies, live crayfish and possible various worms and shrimp. Pick a feeder large enough for your channel cat, and release it into the tank.
Feeding Your Channel Cat
The rule for how much to feed your channel catfish is simple: Regardless of size, feed them only what they can consume in a few minutes. Extra food will go uneaten and pollute the tank. Small, young fish thrive when you feed them once or twice a day. Fully grown channel catfish need fewer meals. You can feed an adult channel catfish one to three times a week. Channel cats are most active in the evening; this is a good time to feed them.