What Do Feeder Fish Eat?

Goldfish are the larger of the two types of feeder fish used in the aquarium hobby, providing food for larger ornamental fish; the smaller of the two are typically non-fancy guppies or tetras. Take care when feeding your aquarium fish feeders, which can contain parasites. At most, make them an occasional food source. Feeder fish have a similar diet to that of larger fancy fish. If you keep them in a separate breeding tank, you can easily feed them basic flake foods.

  1. Flake Food

    • Feeder fish, like regular goldfish or tetras, readily accept basic flake foods as the staple of their diet. If you breed your own feeder fish, flake foods in the feeder aquarium provide the right nutrients to help maintain the feeder fish's health until you transfer them to the main tank. Tetra-min produces inexpensive fish flakes that are readily available in stores.

    Algae

    • Feeder fish will feed on naturally occurring algae within their fish tank, effectively supplementing their diet and contributing to the health of the feeder fish. Algae begins to grow in the tank when you expose nutrients from uneaten fish food and other waste materials to sunlight. Too much algae in the tank can be dangerous for the fish's health, however; never consider algae a staple food even for feeder fish. In the best possible cases, the fish will only eat some of the algae, preferring flake food.

    Leftovers

    • Feeder fish introduced to the main tank that manage to avoid becoming prey for the larger fish in the tank will often feed on the leftovers in the tank left behind after the larger fish have finished eating. These leftovers may include pellet food intended for the larger fish that has made its way uneaten to the bottom of the tank, or remains of other feeder fish missed by the larger fish. In this way, some feeder fish can survive in the main tank until they have grown to a length at which the larger fish will no longer see them as a source of food. This situation is relatively common with goldfish but never with tetras.

    Fry

    • Fish raised in a holding tank will usually eat the young of other fish in the tank or even their own young. Plant holding tanks with hiding places for juvenile fish to allow them to grow to an appropriate size for introduction into the main tank. In this way, you can provide a nearly inexhaustible supply of food for your larger fish without having to resort to the purchase of pet store feeder fish, which often contain diseases such as worms your other fish can contract.