Koi Fish Food: 19 Important Questions Answered

What do koi fish eat? What can they eat, and what would they prefer to eat? What can they eat in the wild and in our aquariums?

We’ll take the time to answer these questions and more.


Koi Fish

What Do Koi Fish Eat in an Aquarium?

Most of us have aquariums much smaller than a koi pond. This would make fish pellets designed for their dietary needs the best choice for feeding them. You can throw in small pieces of fruit or salad greens for variety, but never so much that it falls to the bottom of the tank and/or rots.

To give them protein that mimics the insects they’d eat in a koi pond, you could give them silkworms, earthworms, tadpoles and bloodworms. Do not give them maggots.

What is the Best Koi Food?

The best koi food would be a fish pellet or floating food “stick” made just for them. This ensures that they get all of the nutrients they need eat every feeding. If you are feeding your koi fruits, protein and vegetables on a regular basis, make sure you give them at least one feeding a day of just Koi fish food.

What Can I feed My Koi Fish Besides Fish Food?

That is actually a very long list. You can feed the koi pieces of bread and cooked pasta, fish foods and insect larva, a wide array of fruits and vegetables.

You can cut up shrimp from your table or throw in a variety of worms for them to eat.

Don’t give them too much of any high-fiber fruit or vegetables; they may like peas, but it has a laxative effect so do not give it to them more than once a day every few days.

Do Koi Fish Eat Mosquito Larvae?

Yes. And if there are mosquito larvae in the koi pond, don’t use pesticides to kill the larvae because this could hurt your koi.

Do Koi Eat Duckweed?

Yes. Duckweed is actually one of their favorite foods. If your koi are in a pond with duckweed, you don’t need to feed them as much. And they’d benefit more from foods like oranges and shrimp than vegetables and salad greens.

What Human Food Can Koi Fish Eat?

Koi are omnivorous – they’ll eat both plant and animal matter. They’ll eat small bugs and insect larva. They’ll eat fish food made just for them, and a wide range of fruits and vegetables. They can eat hardboiled eggs, too, though you have to remove the shell.

Can Koi Eat Bread?

Bits of bread are fine. A whole slice of bread may be partially consumed by a fish and devoured by a group of koi. Koi love cereal like oatmeal flakes.

Whole grain pasta and rice is a healthy treat for them. However, you should not give them raw pasta and rice. Instead, cook it and then give it to them.

Don’t cook it in salt, though, because the koi will get too much salt through the food when they eat it. They shouldn’t be given corn because it is hard to digest, though pieces of cornbread are more easily tolerated

They’ll prefer carbohydrate rich foods in the late fall and early spring. In the summer mating season, they’ll prefer high protein foods.

What Fruits and Veggies to Feed Koi?

A short list includes but is not limited to cabbage, tomatoes, pineapple, berries, kiwis, sweet potatoes, lettuce, radish tops and broccoli. If you want to give them vegetables like peppers or tomatoes, it will be better if you cook them first. Conversely, you shouldn’t give them peas, beans or corn at all. This is hard for them to digest.

Know that any vegetables, fruit and grains are giving them needed fiber and micro-nutrients, but the main source of nutrition for koi in a fish tank should be their fish food. So feed them their fish food at least once a day while giving them a variety of additional foods.

Can Koi Eat Apples?

Yes, and you don’t have to remove the skin for them to eat it. Take care to wash the outside so you don’t accidentally introduce pesticides or other chemicals to the koi pond or fish tank.

Can Koi Eat Oranges?

Yes, though you must remove the skin. Verify that the fruit floats in the water before you give it to them. Some fish will nibble at it, while others will ignore it. What they don’t eat should be thrown away. The same is true for lemons, which they can also eat.

Can Koi Eat Banana?

Koi are unusual in liking both vegetables and fruit. They’ll generally try to nibble at pieces of banana. Remove the skin before feeding it to them.

Can Koi Eat Lettuce?

The short answer is yes, they’ll eat any type of lettuce. You could even put in a whole head of lettuce and watch the koi nibble at it. Remove what is left after five minutes, because they’re probably done at that point.

Can Koi Eat Carrots?

Yes. Cook it before giving it to them so it is easier for them to eat. Another option is throwing in frozen carrots after they’ve thawed, since the food processor steamed or cooked them before freezing them.

Can Koi Eat Blueberries?

Yes. Koi can eat blueberries. Since they can handle the shells on shrimp and insects, they could handle the skin of a blueberry. You can increase the odds they’ll eat it by cooking it first, so that it is soft.

Can Koi Eat Spinach?

Very much so. You can cook it or you can put the spinach leaves in the water and watch them eat it. Just rinse the spinach before you put it in the fish tank or koi pond.

Can Koi Fish Eat Goldfish Food?

Small koi will be happy with goldfish flake food. Larger koi want pebble food or solid food. The best thing to give them is Koi fish food.

How Often to Feed Koi Fish?

You have to feed them at least daily. More than once a day is better for them, and it can be highly entertaining to feed them a variety of foods.

How Many Times a Day to Feed Koi Fish?

You can feed them up to four times a day. Only feed them as much food as they can consume in five minutes. Then remove whatever you put in the aquarium or fish pond so it doesn’t rot.

Since fish have a short memory, feeding them several times a day helps them remember you as a feeder and keep them in the habit of approaching you when you arrive.

How Long Can Koi Fish Go Without Food?

This actually depends on their environment and how it impacts their metabolism. In the winter, koi fish in an outdoor pond will have their metabolism slow down. Large fish in this state may not eat for weeks.

Active fish swimming around in the summer will need to eat daily. Koi in a fish tank should be fed daily.