Most aquarium fish are omnivores: you can feed them meat or plants, or both. These species — including goldfish, mollies and catfish— also like eating flake food. If you have goldfish, look for a food formula made just for them.

What do fish eat in the sea?

There is a diverse variety of fish in the ocean that eat small crustaceans, like krill, crab, barnacle, prawn, shrimp, lobster, etc. to large mollusks and invertebrates. Other foods that fish eat include small fish, seals, sea lions, and certain sharks had been seen attacking whales.

What do small wild fish eat?

Goldfish in particular are known to be opportunistic eaters, and will eat plants such as water sprite and duckweed, crustaceans, insects and aquatic macroinvertebrates (such as caddisfly, mayfly, and mosquito larvae), and tadpoles.