How Long Can Koi Fish Live Without Food?

Koi fish are a hardy and long-lived species, with an average lifespan of 20-30 years. However, without food, they can only survive for a few days. It is important to provide them with a regular, balanced diet in order to maintain their health and longevity.

Learn about the lifespan of Koi fish and how long they can survive without food. Discover tips on proper feeding and care to ensure your Koi fish live a long and healthy life.

How Long Can Koi Fish Live Without Food

How long can koi fish live without food?

Understanding how long koi fish can go without food is greatly dependent on the season. The amount of food a koi needs depends largely on its age and size, as well as temperature and water quality changes within their environment.

In colder temperatures when natural sources of nutrients are not available in abundance, it’s best to provide supplemental feeding.

During warmer times of the year, when there is an increase in natural sources of nutrition for them to feed off of, Koi generally do fine with less regular meals or even no supplementary feeding at all.

Basically, Warmer climates will enable them to survive for longer periods without food because it increases their metabolic rate and helps with digestion.

In colder climates, koi may not be able to survive more than two weeks without being fed as there is less energy available due to lower temperatures.

It’s important therefore, if you live in a cooler climate or plan on taking your koi outside over winter, additional feeding may be necessary every couple of weeks or so during this period.

Factors affecting koi fish living without food?

Fish are cold-blooded in nature, meaning they have a limited ability to regulate their body heat. They can’t directly absorb the sun’s heat through their skin or bodies which is good for keeping fish at an optimal temperature for survival.

The factors that affect how long your koi can go without eating depend on different aspects are discussed below:

Impact of climate

In the spring, summer, and fall, your koi fish may not eat as much. This is because their metabolism speeds up to conserve energy when it is cool outside, so they don’t need food if they are well-fed.

Similarly, if there is a warm spell in midsummer, the fish begin to eat more and spend more time swimming around the pond.

Water temperature

Water temperature is an important factor in how long koi fish can go without eating. As the external temperature drops, so does the water temperature, and this affects how much your koi fish eat.

There are known changes in how your koi eat based on temperature, but cold water isn’t the only thing to slow down a koi fish’s feeding.

They also respond adversely to quit high temperatures, so when water exceeding 95 degrees Fahrenheit, koi fish eating habit will decrease

What to feed koi and when?

Koi fish are living beings that need to eat regularly in order to stay healthy. In the summer, when their tanks are warmer than their indoor home, feed them twice a day.

In the winter, when it’s cooler outside and food may cost more, reduce the frequency of feeding to once a day or even every other day.

Koi fish summer food

Keep your koi fish healthy and happy this summer by feeding them a variety of foods throughout the day. Koi fish are omnivorous, which means they eat both plant and animal matter.

The most important thing to know is that each fish has a different nutritional requirement, so feeding them more food than they need could have negative effects on their health.

Koi fish winter food

Koi fish feed on a wide variety of foods. However, if your pond is experiencing temperature fluctuations, you may want to switch the type of food you feed your koi fish to help them keep up with changes in water temperature.

Some high-quality cold-weather fish food looks for wheat germ early in the list of ingredients.

What are the common food items koi eat?

Koi fish are known to be very easy to care for and they are easy to feed. They have fleshy mouths which make them better at capturing prey than other types of fish.

Koi can be fed with a variety of food; whole earthworms, insects, insects eggs and larvae, mealworms, prawns, and snails are some examples. Discuss below the common food items koi eat:


Although it is true that koi fish are known for eating algae, they aren’t big algae eaters. Rather, they may eat more insects and fish food while sometimes eating a few algae.

Koi fish are best used in combination with other algae eaters, such as pleco and gourami.

Silkworm pupae

There are many reasons why koi breeders choose silkworm pupae as a natural food for their koi. From most biologists’ point of view, they are one of the healthiest feeders around because they are rich in calcium, protein, and B vitamins.

They also contain very little fat, which helps in maintaining a healthy body condition.

Bloodworm larvae

Bloodworm larvae are a tasty treat for fish and other pond animals. They are high in protein, which is important for healthy koi.

Bloodworms can be raised in your own backyard, or purchased from a local pet store.


Live food is an important part of the diet for most freshwater aquarium fish. While mealworms, crickets, and earthworms are some of the easiest live foods to feed your koi, your fish will also enjoy small crustaceans, insect larvae, and a variety of other worms.

Therefore bloodworms, tadpoles, and shrimp can be healthy food for koi.


Koi can be very picky eaters. They prefer long, slender plant material (stems, leaves, and roots). When feeding on floating plants like hyacinths, their teeth scrape through the skin and eat into the nutrients of the plant.

Free-floating plants are not as tasty as rooted ones because they have thicker skins.


Duckweed is a type of aquatic plant that has been an important food source for koi and other pond fish, like goldfish (not to be confused with goldfish).

Duckweed has also become an important food source for people who own koi ponds or have koi ponds as part of their landscape.

Duckweed is high in protein that closely resembles animal protein than most other vegetable proteins, plus duckweed is also high in other important nutrients making it an ideal food for koi.


What happens if you don’t feed koi?

Koi are carnivorous animals and need to eat 7-8 times a day. If they don’t get enough food, koi can go into hibernation, so they must eat and store nutrition as much as possible during the summertime. If they do not eat enough, many times, they go into winter in poor health and that may result in sickness in spring.

What temperature does koi stop eating?

As the water temperature falls below 50 degrees, your koi will only eat two to three times weekly. This is because they are in a state of hibernation and don’t need to eat as much. As the water temperature gets below 41 degrees F, you’ll stop feeding your koi altogether because it’s time for them to be in hibernation mode.

Can koi eat bread?

Koi fish should never be fed bread, peas, or corn. These are high in carbohydrates and will ruin their health. Their best food is chopped lettuce or spinach (not from your garden though) but only if you can get it low on the oxidation scale. Other bugs you caught in the wild would work as well, but try to avoid them dying in your pond because that’ll make it smell bad.

Are koi fish always hungry?

If you’re having a hard time deciding if your fish are always hungry or not, it’s probably because they aren’t always hungry. While this may seem confusing, fish do have the instinct to eat. They may act like they need food even when they don’t because their brain tells them they need food since they see other fish eating and reproducing.

A good rule of thumb is never to overfeed your aquarium as it could cause medical problems in the long run such as digestive issues and stress caused by over-breeding of good genes because they won’t be able to get rid of excess nutrients from their system.

What is the best natural food for koi?

Koi are fed protein pellets, cereals, and seeds to give them the aforementioned essential nutrients. Carbohydrates for koi include fruits and vegetables such as squash, peas, and watermelon.

When feeding your koi, it is important to monitor your fish’s diet often by closely observing their health. For example, if your fish’s gills are turning red rather than pink then you know it’s time to spread out their feed, which can happen with hardy fish like koi very quickly. Also, be sure to don’t overfeed your fish because if they can’t get rid of the extra food they will grow too fast and become unhealthy.

Finale Words

Koi fish can survive up to two weeks without food, but their survival rate beyond this depends on the temperature of where they are living. Warmer temperatures will result in koi being able to go a little longer than two weeks before needing to be fed again. In more extreme climates like very cold or hot environments. Hopefully this article helps you to know how long can koi fish live without food?


  • Blessin, Heiko. “Seasonal feeding for koi: nonsense or really important?
  • “Nutritional, functional, and allergenic properties of silkworm pupae.” NCBI
  • “TPWD: Warm- and Cold-Blooded Animals — Young Naturalist.” Texas Parks and Wildlife
  • “What Do Koi Fish Eat? (How And What To Feed Them).” Coachella Valley Preserve.