What do goldfish eat? Surprising things your fish will feed on

Two goldfish swimming in tank
(Image credit: Getty Images)

What do goldfish eat? Well, as it turns out, our little finned friends have quite the expansive palette! Goldfish are one of the most popular pets all over the world, and they can live a surprisingly long life, especially when kept in the best fish tanks and fed the correct diet. 

Although most pet owners will likely buy commercially-available fish food for goldfish kept in tanks at home, they are actually omnivorous and can eat quite a wide variety of different foods. That includes things like algae, insects, vegetables and insect and fish eggs. In the wild, goldfish would be constantly foraging, but in fish tanks they’ll obviously be limited to what you give them. In fish ponds, they might have a few more options, but you can still supplement their food with extra treats.

It’s a good idea to give your goldfish different types of foods, not only will it give them the nutrients they need to be as healthy as possible, but it’s likely to also keep them happier than if they are only fed the same thing on repeat. Let’s find out more about the typical things that goldfish like to eat.

Can goldfish eat tropical fish food?

Goldfish are not particularly fussy, and in the wild will eat pretty much whatever they come across. If for some reason you have tropical fish food already - perhaps you also keep tropical fish (you shouldn’t keep them in the same tank - we recommend the best tropical fish tanks for our bright and bold finned friends), and you find yourself in a bit of a pinch, then you might be wondering if it’s safe for your goldfish to eat tropical fish food. 

The short answer here is yes, they can eat it. There should be no immediate problems with feeding your goldfish tropical fish food, but since it hasn’t been specifically formulated with this kind of fish in mind, it’s not a good long-term solution. You should stock up on more appropriate food next time you can. 

Will goldfish eat shrimp?

As already mentioned, goldfish are omnivores, which means they eat a wide variety of different foods - including other fish. 

That said, they are also limited by the size of their mouths. That means if you keep certain types of shrimp in the same tank as your goldfish, you could find that they make for a tasty snack. 

Goldfish which are kept in tanks and have an abundance of other easier-to-catch food available to them (such as flakes) may ignore shrimp that is kept in the same tank as them, but they might not. 

If you want to keep shrimp in the same tank as your goldfish, giving the shrimp lots of places to hide - such as artificial plants or these best fish tank accessories - from the goldfish will give them the best chance of survival.

For those using the best small fish tanks, it’s probably a good idea to keep shrimp out of the equation altogether.

Will goldfish eat other fish?

Goldfish swimming in tank

(Image credit: Getty Images)

Again, as goldfish are omnivores the simple answer is yes - they will eat other fish. But, only if the other fish is smaller than the goldfish's mouths. Very small fish may be accidentally swallowed while the goldfish is moving around the tank looking for food.

That means it should be perfectly fine to keep other similar sized fish in the same tank as your goldfish. It’s important to make sure that fish of a similar temperament are kept together - if you’re not sure, make sure to ask your breeder. 

Goldfish are not particularly aggressive or prone to attack - so you shouldn’t find that goldfish start to eat other goldfish, or other similarly sized fish.

That said, to make the environment as stress-free as possible, you should make sure there’s plenty of space for each fish to occupy, and that the water temperature and quality is appropriate for the type of fish inside. For example, it’s not a good idea to keep tropical fish and goldfish together since tropical fish require much warmer water.

What’s the best food for goldfish?

If you’re not sure what the best fish food for goldfish is, then the key thing to think about is variety. In the pet store, you’ll likely be faced with a choice of flakes or pellets, while you may also see fish gel, which is closer to what goldfish might eat in the wild. 

All of these are usually good choices for goldfish. Be sure to look for those which are specifically formulated for goldfish if you can, or at the very least are designed for lots of different types of fish. 

You can also supplement this easy-to-use food with other types of food which should be a good treat for your goldfish. Examples of this include freeze dried options such as bloodworms, live food such as small shrimp, glassworms, snails and frozen options like algae, krill, shrimp and bloodworms. 

It might come as a surprise to learn that goldfish can also eat some of the same foods as us. Green vegetables like broccoli, potatoes, peas and zucchini can be fed - but they should be boiled first to make them nice and soft and easier to eat. 

With all this in mind, it’s also important to remember that you shouldn’t overfeed your goldfish. As constant scavengers, they will eat pretty much whatever is put in front of them - and won’t stop. You should also space out their feeding times, to ensure they don’t eat too much too quickly. 

It’s also important to make sure you’re regularly cleaning your goldfish’s tank to remove any remaining food to ensure the best quality of water for your fish. Keep your scaly friend happy and healthy and you might be surprised by how long goldfish live

Amy Davies

Amy Davies is a freelance writer and photographer with over 15 years experience. She has a degree in journalism from Cardiff University and has written about a huge variety of topics over the years. These days she mostly specialises in technology and pets, writing across a number of different titles including TechRadar, Stuff, Expert Reviews, T3, Digital Camera World, and of course PetsRadar. She lives in Cardiff with her dog, Lola, a rescue miniature dachshund.