What Do Goldfish Eat? Everything You Need to Know

Goldfish (Carassius auratus) are a domesticated species of carp with a rich history, originating in China over a millennium ago. Historically, goldfish were prized by Chinese and Japanese royalty. Today, there are over 200 distinct breeds of goldfish, which gained widespread popularity as ornamental pets in the late 19th century, as they became more widely distributed and readily available. Continue reading to discover everything you need to know about what goldfish eat.

What Foods Do Goldfish Eat?

Goldfish eat insects, plants, and crustaceans. These omnivores are opportunistic feeders that have a bit of trouble with self-control; they’ll eat as long as food is available.

Goldfish are adapted to eat small amounts continuously, which makes them efficient foragers. However, they will also take advantage of large food sources when available. Although goldfish can overeat, severe health issues such as bloating and swim bladder problems are less common in the wild, where food is more varied and less concentrated.

Among the foods that they will gorge on are:

• Algae
• Zooplankton
• Mosquitos
• Tadpoles
• Decaying plant matter
• Worms
• Fish eggs
• Blood worms
• Brine shrimp
• Mysis shrimp
• Water fleas
• Baby lobsters
• Water lettuce
• Anacharis
• Insect larvae
• Insect eggs

These are just some of the more common foods that goldfish eat throughout their lives in the wild. Most of the time, wild goldfish eat insects, insect larvae, plants, and the eggs of insects or other fish.

What Do Captive Goldfish Eat?

Although they were first selectively bred in China over 2,000 years ago for food, goldfish are more commonly seen swimming in home aquariums these days. They are very common pets, valued for their beauty and ability to flourish in conditions that are less than favorable to other fish.

Typically, they are either kept in aquariums or domestic ponds, though they are also found in natural waterways, as a result of being discharged by irresponsible owners. When kept in captivity, a goldfish’s diet differs significantly from that of a wild goldfish or carp. Foods that pet goldfish eat include the following:

• Algae wafers
• Brine shrimp
• Bloodworms
• Commercial food pellets
• Lettuce
• Aquarium Snails
• Peas
• Kale
• Daphnia
• Spinach.

Goldfish can consume each of these foods, though most owners are content to feed their aquarium goldfish commercial food in the form of pellets or flakes. When they are kept in ponds, goldfish may also receive supplementary foods such as chopped vegetables, algae wafers, and commercially available dried insects.

Goldfish kept in ponds will also feed on insects, such as mosquitoes, that come near the water. It is important to monitor a goldfish’s diet and provide only enough food to meet its nutritional needs.

How Much Does a Goldfish Eat?

A goldfish in captivity has specific dietary requirements. If a goldfish is being fed food pellets, as many are, it is best to feed them two to three times per day, following the directions on the packaging.

It is important to remember that goldfish generally do not know when to stop eating, so goldfish owners need to provide an adequate amount of food to avoid overfeeding.

In the wild, goldfish are constantly foraging, expending massive amounts of energy, so they are less affected by issues such as water quality and limited space.

What You Should Not Feed Your Goldfish

Both wild and captive goldfish need to avoid some foods, including:

• Bread
• Generic fish food
• Crackers
• Cereal
• Beef
• Pork.

Bread, crackers, and cereal can cause bloating in goldfish, which can be fatal in extreme cases. Generic fish food tends to lack the nutrients goldfish need and clouds the water more than foods specifically made for goldfish. Although goldfish are omnivores, they should avoid foods like beef and pork because these are high in fat, which can pollute the water and cause liver damage.

What Predators Eat Goldfish?

Goldfish can grow quite large in the wild, and their bright colors can be a tempting target for a predator seeking a good meal. Some of the most significant goldfish predators include:

• River Otters
• Beavers
• Possums
• Herons
• Hawks
• Dogs
• Domestic cats
• Skunks
• Bobcats
• Mountain lions
• Cougars
• Raccoons
• Snakes.

These animals may find goldfish in the wild and pluck them out of the water. The danger to them doesn’t end when people place them in an artificial pond, either. If a hawk can spot a goldfish from above, it will attack.

Humans could be considered predators of goldfish because they keep them as pets, sometimes in less-than-optimal conditions, but goldfish are technically edible and have occasionally been eaten, but this is rare and not a common practice.

These beautiful fish are common sights in aquariums and ponds around the world, and they can remain healthy as long as their owners understand what and how to feed them.