How Long Do Koi Fish Live?


The fish breed is famous for its considerably long longevity. Besides, there are various factors to last the Koi’s life span as long as possible.

Today’s post, “How long do Koi fish live” will tell you all the useful methods about the lifespan of Koi fish that you need to notice. Are you wondering what they are?  Keep reading!

How Long Do Koi Fish Live?

The lifespans of Koi fish will basically be classified into three types:

Koi are raised in perfect conditions, including these features below:

  • Optimal water source quality
  • Ideal pH grade
  • Full nutritional level
  • Decline stress

Koi’s longevity can be up to 50, 60, or 90 years. However, Hanako is an exception with the life-lasting to even 226 years!

Koi fish are raised in an artificial environment with a short life in a range of 3-5 years. The fishkeepers may have some difficulties in essential skills and fish knowledge, the lifespan of these Koi has significantly decreased as a result.

Koi fish may live up to over 25 years if being kept by these collectors. You are probably curious about the reasons for the big difference, although this longevity is still quite short. There are many reasons below, which can reduce the lifespan or even kill Koi fish:

– The majority of Koi live longer than their collectors

– Losing discipline to maintain the pond

– Depending on other factors for living conditions

Many fish breeds, not in Japan, have up to 15-year life expectancy, while Koi fish originated from the Japanese might live up to about 40 years.

As you can see, the Koi fish’s longevity depends on different conditions. Especially, external elements we will mention below.

What Is The Most Important Factor Deciding Whether Your Koi Lives Long Or Not?

Regardless of how well your pond environment is, nothing is as vital as genetics.

Japan is the leading nation in Koi nurture. The international Koi sciences have continuously studied to find out the best way to improve the gene source, but the fish breed from Japan still has longer longevity than other countries.

Once the Koi of Japan was debuted to outside nations, Japanese Koi with the greatest quality did not lose their first status in legacy maintenance. Many leading breeders successfully crossed a new fish line from genes of imported and domestic Koi breeds.

Globally, the Japanese Koi are reportedly remained to hold the record of “longest lifespan” of all varieties of ornamental carp.

And why do Japanese koi have the longest life fish among other ornamental carp lines? Probably because of these external reasons below:

Koi-raising knowledge in Japanese culture

Western breeders have considerably less experience in upbringing Koi fish varieties than Japanese.

Japanese culture dominates the fish-keeping method, with valuable traditional knowledge being inherited from many long fishkeepers generations.

Ancient Japanese Koi genes

Japanese cultivators were the initial breeders of the modern and new ornamental carp breed in Japan. It proves that they take the first opportunity to choose the best koi specimens, which maintains the diversity and tame of Koi’s genes.

Hibernation in Japanese Koi

The Hibernation is a stage in the life cycle of Koi fish to when winter in Japan becomes cold and severe.

Hibernation helps Koi fish reduce metabolism speed and save energy in some months per year. This habit is one of the significant factors impacting Japanese Koi’s longevity.

How To Increase Koi Fish Longevity By Setting Up An Ideal Tank?

Besides the remarkably long life expectancy of Koi fish compared with other aquarium fishes, these Japanese fish breeds also have stronger resilience in harsh environments. Provided that people care properly, the longevity of your pet fish can last 25-35 years.

You can refer to one of these following ways to meet the requirements of a great aquarium making the Koi’s lifespan longer:

  • Filter and water quality

A water purifier for the fish tank operating at least 3 times a day is necessary to run the aquarium’s whole capacity.

Koi is strong enough to live in poor environmental conditions but pay attention they are poisonous easily with ammonia in some cases. Specifically, 0.25ppm is the lowest level causing death.

  • Tank size and set-up

Koi fish are an energetic species, active all day but less at night to seek food.

The size of the fit aquarium will be determined by the different ornamental fish you keep. Some following introductions that you can refer to:

Fish Types Aquarium Requirement
Juvenile koi fish 30-50 gallons
Mature koi fish at least 100 gallons/fish  –   36 inches deep
Mature koi fish (single) 200 gallons/fish
Mature koi fish (a group) 1000 gallons  –   72 inches deep

Keep in mind to avoid laying the tank directly under sunlight or in too cold condition.

Besides, always close your tank’s lid tightly because, in some situations, these koi fish are messy to jump out of water.

If you are going to keep 2-3 mature koi fishes in an aquarium, add 2 or 3 single ones first. The initial mess or sudden line of waste may cause an imbalance regardless of in a well-prepared aquarium.

  • Diet

Koi is a kind of greedy fish. It is difficult to identify exactly the content of oversized feeding for ornamental fish of this size.

These fish keepers are advised not to feed koi fish too much to prevent obesity because this situation will considerably negatively affect the longevity of this Japanese fish breed.

Read more: Best Koi Food

  • Temperature

Keeping koi fish in a deep pond will reduce metabolism speed during the hibernation period underneath the ice.

This stage can considerably last longer their lifespan. 65-75°F is a suitable range of temperature in a tank that you should maintain.

  • Substrate

Substrate a large muddy layer in the bottom to simulate the wild environment as carps survive in nature.

The majority of fishkeepers don’t lay aquatic plants in koi tanks because the root will be dug continuously.

  • Lights

Set light to illuminate your aquarium. Follow a daily schedule, 8-10 shining hours every day.

And with these outdoor ponds, which should have shade from the trees, for example, so that your koi are able to hide in summer days.

  • pH

7.0-9.0 is a range of pH levels that you should keep for a water pond.


This Japanese fish breed has noteworthy longevity. But it is impossible to identify how long their life can last. Probably time will give you an answer you are finding.

Hopefully, these details knowledge of “How long do Koi fish live” can help you obtain your achievement, that’s keeping Koi fish successfully for the few future decades. Thanks for your reading!

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