What Do Catfish Eat in a Fish Tank? (9+ Foods)

what do catfish eat in a fish tank

As exotic and appealing aquatic pets as catfish are, many novice aquarists wonder what do catfish eat in a fish tank. Catfish can thrive on different diets, including sinking pellets that turn mushy, fish flakes, crude protein sources, and live or frozen foods.

Of course, you will want more detailed answers to the type of catfish aquarium foods you can give. So, continue reading to learn more.

Foods You Can Give to Catfish in a Fish Tank

In general, catfish is a bottom feeder, happily digesting anything it can get into its mouth at the fish tank’s bottom, including smaller aquatic species. Given how some catfish species can grow up to 3 feet long, it’s not really surprising that catfish eat other fish in tank as well.

Catfish will devour almost anything you put in front of its mouth. But is that the correct way to care for catfish species? The following foods make excellent nutritional sources for your pet catfish.

1. Aquarium Feed


Catfish feed at the bottom, and they do not devour floating food. Hence, the aquarium catfish food must sink to the fish tank’s bottom.

You have two options: sinking pellets and fish food flakes. Most aquarists recommend the former because it “sinks” to the bottom, allowing catfish to scoop the pellets up with its vacuum-like mouth.

Sadly, most fish pellets are too hard for catfish to eat. Hence, you might want to look for an aquarium feed that turns mushy or breaks apart as it sinks to the fish tank bottom.

If you have an upside-down catfish, know these species feed at the aquarium’s top. Hence, you might want to give them fish food flakes, which float on the water’s surface. Over time, these fish foods will sink to the bottom and become a diet for bottom-feeding catfish.

2. Frozen Dried Food


Freeze-dried or frozen brine shrimp, Mysis shrimp, Tubifex worms, and bloodworms are a favorite part of the catfishes diet. A steady meal of high-protein foods can help catfish grow an inch every month.

You can break or chop the frozen food block into tiny bits and toss them into the aquarium. Wait for them to sink and watch your catfish devour these yummy treats.

Frozen catfish food come in various sizes. So, we recommend feeding your catfish accordingly. Large catfish species will want larger food portions. You can also feed baby catfish frozen food, albeit in a smaller amount.

3. Small Worms and Insects


Bait worms, bloodworms, and other small live worms can also become excellent nutritional sources for catfish. You can buy these catfish food from feed stores or even bait shops.

Drop them into the aquarium, and the worms will sink to the bottom. Catfish then scavenge these worms.

Meanwhile, small catfish species love insects, including caddisflies, dragonflies, mosquito larvae, dragonfly larvae, and mayflies. More than half of their diet can consist of insects.

4. Small Crustaceans


Small crabs, shrimp, lobsters, and crayfish are all favorites of catfish, provided they fit into the catfish’s mouth.

So, if you have small crustaceans at home, you can drop a few live ones into the water and watch your catfish hunt for these shelled aquatic creatures.

5. Feeder Guppies


Some catfish keepers recommend feeder guppies to help provide crude protein to the catfish. Although this food item might be costly, it would be interesting to watch catfish hunt and devour guppies.

You can buy these feeder fish from your local bait store. A pet shop might also have them. Introduce a few feeder guppies into the fish tank and watch what happens.

6. Sardines


Some aquarium catfish eat sardines, small perch shad, herring, bluegill, minnows, and other small fish species. However, these should only be feed to large species, not small ones

Your local bait shop should have sardines in its stock. After all, it is a favorite bait for catfish anglers. Alternatively, you can also opt for canned sardines, but only in a moderate amount.

7. Small snails


Many aquarists consider snails as pests in fish tanks. Hence, adding catfish to your aquarium should be a natural pest control.

And if your aquarium does not have snails, you can always purchase them at a shop and feed them to catfish.

8. Rotten Cheese


Catfish are omnivores, devouring anything on its mouth’s path. A tiny bit of rotten cheese should make for a yummy (albeit smelly) treat.

The cheese’s weight should help it sink to the bottom, allowing the catfish to scavenge it.

9. Other Foods

So, what other foods do catfish eat in captivity? Catfish can eat almost anything, including uneaten fish food, algae, organic debris, and other stuff. They can also eat water lilies and duckweed.

As catfish are bottom feeders, we recommend removing leftover fish food from the substrate to avoid overfeeding the species. That said, if the leftovers are not too excessive, let the catfish clean aquariums.

The following table summarizes the food for catfish. Again, we must emphasize that except for upside-down species, these are bottom feeders, so you should never give anything that floats when you feed catfish in an aquarium.

[su_table responsive=”yes” fixed=”yes” class=”productable”]

Catfish Food TypeFood Item
Aquarium feed
  • Fish flakes
  • Sinking pellets that turn mushy
Frozen food
  • Mysis shrimp
  • Brine shrimp
  • Bloodworms
Live food
  • Small crayfish
  • Bloodworms
  • Bait worms
  • Feeder guppies
  • Sardines (canned sardines are also okay)
  • Small snails
  • Small insects
Other food
  • Rotten cheese
  • Algae
  • Any food that sinks to the bottom


Nutritional and Food for Feeding Catfish in Fish Tank


Here are a few guidelines to ensure your catfish has the correct nutrition for optimum health.

1. Crude protein is a must in a catfish’s diet.

Although omnivores, catfish are essentially meat-eaters. They need more proteins in their diets than carbs and fats. Hence, aquarists must read the ingredient list of aquarium fish food (i.e., pellets, wafers, and flakes).

Consider it a deal breaker if the fish food does not list proteins in the ingredients. The crude protein content should be at least 20 percent. Hence, giving small fish, crustaceans, mollusks, insects, and worms should provide a catfish’s protein requirements.

2. Choose catfish food that softens and sinks to the bottom.

Unlike other fish species with mouths in front of their heads, catfish mouths are somewhat on the underside. This unique anatomy makes it impossible for most catfish species to catch and eat floating fish food.

So, what kind of food do catfish eat? The kind that sinks to the bottom is ideal for catfish species. Moreover, the catfish food must turn mushy as it sinks to the bottom. Catfish cannot “bite” and “chew” hard pellets. Otherwise, they will have indigestion.

3. Learn the catfish’s behavior by watching them feed.

Most catfish species are part of a larger fish tank community. Although most species can get along harmoniously with tankmates, aquarists must recognize that catfish can also eat other fish.

Catfish species have varying personalities. Some are docile, while others are vengeful. You might want to observe your fish during feeding and note any unwanted behavior.

How to Take Care of Catfish


Knowing what catfish eat is part of its care. Here are additional pointers to ensure a happy catfish-keeping journey.

1. Recommended Catfish Species

Many aquarists recommend the Cory, Glass, Pictus, Upside-down, Otocinclus, Bristlenose, Clown, Striped Raphael, Bumblebee, and Chinese algae-eater catfish because they are more docile than the Red-tailed and Common Pleco catfish.

2. Ideal Aquarium Plants

Choose bottom-dense and heavily-rooted aquatic plants for your catfish. These plants offer a safe refuge for your fish from intense light. Popular choices are bogwood, anubias, Vallisneria, Amazon swords, water sprite, and Java fern.

3. Suggested Tankmates

Catfish should live with similarly-sized fish species and with similar temperaments. Excellent choices include the Opaline gourami and giant danios. You can also include large platies and rainbow sharks.

4. Ideal Substrate

Catfish are bottom dwellers, spending most of their time scraping the substrate with their undersides. Hence, you can place smooth aquarium sand to make the surface as pleasant to the catfish as possible. Add a few pebbles or rocks to improve the substrate’s aesthetics.

5. Recommended Feed Volume

Remember, catfish scour the aquarium bottom for leftover fish food. Hence, you might want to feed them small portions at first. You can adjust the feed volume to let the catfish finish their meal within ten seconds.


What do catfish eat in a fish tank? Being omnivores, catfish can eat any substance on their mouth’s path. It can include small fish, fish eggs, insects, crustaceans, mollusks, and worms.

Catfish can also feed on aquarium catfish food (i.e., flakes, pellets, and wafers) that turn mushy and sink to the bottom. You can give catfish frozen or freeze-dried fish food, although it is more fun to watch catfish devour live food.