Do Goldfish Eat Other Fish? Yes, And This Is Why

Goldfishes are one of the most popular choices as a pet fish. If anyone has an aquarium, you can bet it will have a Goldfish in there.

A question that lingers in everyone’s mind before bringing in any fish into a tank is how aggressive that fish will be. Many aquarists get concerned before introducing Goldfishes to fish tanks. Will the Goldfishes eat other tankmates?

Goldfish, generally, do not eat larger tankmates. They might, however, try to eat smaller tankmates like guppies, Koi fish eggs, and even smaller goldfishes.

We have the table below that tells you what fishes a Goldfish can and can’t eat for better reference:

OrganismsDo Goldfish Eat Them?
GuppiesYes, big Goldfishes can eat smaller guppies.
Baby MinnowsYes
GoldfishYes, the smaller ones
Mosquito fishNo
Koi fishYes, they can eat their eggs.
Betta FishNo

First Things First – What Does A Goldfish Eat?

Goldfish are omnivores in the wild. They eat plants, insects like mosquito larvae, tiny crustaceans, zooplankton, and decaying plant and animal detritus found on the bottom.

In captivity, Goldfish are often fed a dried flake or pellet diet. Other diet supplements include freeze-dried Tubifex worms, bloodworms, daphnia, mosquito larvae, brine shrimp, and vegetables like cooked peas and lettuce.

Goldfishes are opportunistic feeders that eat whenever food is available. So, be careful not to overfeed them.

do goldfish eat other fish?

Do Goldfish Eat Other Fish?

Goldfish, in general, have a moderate temperament and don’t get aggressive. Goldfish are not violent, so they have no desire to consume one another.

However, changes in their environment may cause a shift in this behavior.

For example, they may consume a baby Goldfish. These fishes lack parental instincts, so they are unable to distinguish their young babies from their food. 

If you keep the parent fishes in the same tank as their fry, there’s a greater chance that they’ll consume their kids. You should separate the parent fishes as soon as the eggs are hatched.

Goldfish aren’t predators, so they don’t go after other fish to eat them. When looking for food, they may swallow smaller fish, exactly like they do with newborn Goldfish.

Why Do Goldfish Eat Other Fish?

Goldfish will devour nearly anything that fits in their mouths.

Part of this is due to their need for personal space. If they feel crowded, they become violent. Goldfish are territorial; therefore, if the tank is overcrowded, they may eat their new tankmates. They will, however, usually try to chase them away first. This will provide you with ample notice that action is required.

Another reason why Goldfish eat other fish is due to their lack of parental instincts. They just can’t tell their offsprings apart from other fishes in the tank. However, they eat baby Goldfishes only if they are extremely hungry. In an attempt to obtain edible food, underfed Goldfish may become aggressive and bite tank mates.

Which Fishes Can You Keep Along With Goldfish?

Here is a list of few fishes that you can put in the tank along with the Goldfish:

  • White Cloud Mountain Minnows
  • Betta fish
  • Hillstream Loach
  • Dojo Loach
  • Ricefish
  • Zebrafish
  • Catfish

How to Prevent Goldfish From Eating Other Fish?

Goldfishes are very docile; they won’t attack any other fish if they are fed properly and have enough room for themselves in a tank.

Here are some ways in which you can prevent Goldfishes from attacking other fishes:

1. Ensure Good Water Quality

Poor water conditions means your Goldfish is always stressed, and that can play out in different ways. They’ll sometimes lash out at other fish or even the entire tank if they don’t have anything better to do with their time.

2. Don’t Overcrowd the Tank

Goldfish prefers a tank with more space. They might start eating other fish to make some room for themselves.

As a general rule of thumb, keep in mind that each Goldfish needs 10 gallons of water and add the fish accordingly.

3. Feed Them Properly

It is important to feed the Goldfish the right amount of food. They cannot store their food for long. So, make sure that you don’t leave them hungry.

A hungry Goldfish is an aggressive Goldfish; you better make sure that they are properly fed.

4. Introduce Them Into a New Tank

If you have tried everything and the Goldfish is still after the lives of other tankmates, give her a new home.

This is the best way to calm an aggressive Goldfish.

Frequently Asked Questions

  1. Are Goldfish Aggressive?

    Generally, Goldfishes are not aggressive. However, they may get aggressive if the tank is overcrowded or if they are extremely hungry.

  2. Can Oranda Goldfish Live With Other Fish?

    Yes, you can keep other fishes with an Oranda Goldfish as they are not predators.

  3. Do Goldfish Eat Dead Fish?

    Goldfishes are constantly looking for food, so they will often eat a dead fish if they find one around the tank. They may do this either to clean up their home or because they’re always hungry.

  4. Do Goldfish Eat Other Goldfish Tails?

    Yes, Goldfish try to bite each other’s tails. They do this mainly when they are provoked or if the tank is overcrowded.

  5. Will a Big Goldfish Eat a Little Goldfish?

    Yes, they certainly can eat little Goldfishes. But Goldfish will do this only if they are very hungry.

  6. Are Goldfish Cannibals?

    Goldfishes are not cannibals in general. However, there can be instances when they show cannibalism.

  7. Can a Fighter Fish Live With Goldfish?

    Yes, they can live in the same tank as long as the tank is not overcrowded.

Wrapping Up

Goldfishes are not aggressive. Quite on the contrary, they are quite calm. They are not predators either. So, as long as the Goldfish is properly fed and has a healthy environment, it won’t kill other fishes.

Further Reading