How Long Do Koi Fish Live?

If you are planning to buy a Koi fish that has a colorful variation. They are developed by selective breeding from Asian subspecies. They are mostly known for keeping in a personal garden pond because it has a high life expectancy of around 100+ years. It would be very difficult for you to believe that the life expectancy of their koi fish relies on a caretaker to caretaker. In this article, you would learn how long do Koi fish live. 

Koi Lifespan: How Long Do Koi Fish Live?

Koi Lifespan

On average, the lifespan of a Koi fish would depend on climate. When you keep your Koi fish in favorable climates. With the best quality of water, adequate pH levels, nutritious levels, and low pressure, a Koi fish would be able to live for 50-60 years or even for 90 years. There are many Koi fish such as Hanako who have lived for almost 226 years.

Factors That Affect The Lifespan Of Koi Fish

The following are various components by which the lifespan of Koi fish is influenced:

#1 Oxygen Levels

Lack of oxygen is considered to be one most popular stressors that direct to the unexpected demise of Koi fish. Algae blooms are the only primary aspect that enhances the failure of Oxygen in the ponds of Koi fish. 

During the process of photosynthesis, algae help in generating oxygen in the daytime as a by-product. A large amount of algae is also not good. If your pond is having uncountable algae, they would start taking in Oxygen, which can result in the death of the Koi fish.

#2 pH Level

The pond should have a pH level that lies between 7.0 to 8.6 so that the Koi fish can live comfortably. Hence, you are required to discard all deteriorating foliage and the superfluous food of your Koi fish after feeding to keep the pH level of the garden pond balanced. A water filtration system would be very helpful and effective in this situation.

#3 Nutrition

Nutritional status plays a crucial role in the lifespan of a Koi fish. It has been recognized that an adequate diet for a Koi fish helps in maintaining the overall health and development of your Koi fish. Hence, before nourishing your Koi fish you are required to do proper research and read the inscriptions carefully.

#4 Quality Of Water

You should always provide your Koi fish with water of the best quality for letting your Koi fish live a long life with comfort. The water of your Koi fish pond is required to be free from nitrites, ammonia, chlorine, and nitrates. This would help your Koi fish to be protected from any kind of bacterial infection and your fish could live safely. 

The quality of water can be retained by checking the quality regularly. Home Water Test Kits would be a nice testing kit for maintaining the quality of water. 

#5 Atmosphere 

The lifespan of a Koi fish is also affected by the environment in which they live. There exist three places where your Koi fish would be able to live with comfort.  

  • Outdoor Ponds
Outdoor pond for koi fish

If your Koi fish has a large size, outdoor ponds would be the best option to keep your fish. The Koi pond of 1000 gallons would be a favorable size for your Koi and it should be over 1000 gallons and should have a width of at least 3 feet. 

Furthermore, Koi fish would require an adequate atmosphere with natural and automatic filtration. This is because they are healthy animals. Supervision of the pond water is very essential for keeping your Koi fish healthful and comfortable.

  • Indoor Ponds

Indoor ponds for Koi would be a wonderful expansion to the interiors for your home. Nonetheless, you should be conscious of the area. The larger the pond your Koi has, the better it is. Many additional components would require an adequate appreciation, comprising the lighting, the decorations, the filtration, the heater and much more. Everybody looks for incredible indoor ponds. But people forget that it requires a lot of planning.

  • Aquariums

A fully grown Koi Fish never lives with comfort in aquariums. Hence, we would not suggest aquariums for your Koi fish. Nonetheless, a young Koi could be easily kept inside an aquarium.

Top 3 Oldest Koi Fish In The World

#1 Hanako (c. 1751 – July 7, 1977)


Hanako is the only Koi fish who has lived for the highest year. This fish has become very popular among the Koi fish ever recorded because of its remarkable age. Hanako passed away in 1977. It was recognized that Hanako lived for almost 226 years, giving rise to itself the tag of the oldest koi fish ever in this universe.

#2 Portland Japanese Garden Koi (before 1996 – Present)

Portland Japanese Garden Koi

The Portland Japanese Garden is like a home for around 50 Koi fish. This is considered to be one of the most prominent characteristics of this garden. Since the 1970s there is an appliance in the Koi pond which you can find at the Portland Japanese Garden. From the viewpoint of Senior Gardener Adam Hart maximum, all the gardens have the histories and names of koi fish. 

He also mentioned that almost all the Koi fish have a lifespan of around 30 years in his garden. Adam Hart also said that various tourists used to come and used to ask among all the Koi fish which one is the ancientest. On today’s date, Portland Japanese Garden Koi would be around 22 years old.

#3 Big Girl (c.1990 – Unknown)

Big Girl koi fish

Big Girl is also considered to be one of the oldest Koi fish. In late 2007, a fish called the name Big Girl was becoming very popular for being the biggest Koi fish in the world. This Koi fish had a 40.8 kg weight and had a length of 4 feet, i.e, 1.2 m.


For how many years a Koi fish would live relies on the food you provide to your fish and how you maintain your fish. Hence, it is always recommended for a reliable Koi caretaker to clean the garden pools regularly and provide high nutrition food. Koi normally have a lifespan that lies between 30 to 40 years and sometimes more. 

But there are some unique abnormalities, such as Hanako who lived for more than 200 years. Whatever the age might be, an incredible devotion and supervision would only help to live delighted and have a long-living Koi. We hope this article helps you to get information regarding the lifespan of a Koi fish.

Frequently Asked Questions

How Long Do Koi Live In Captivity?

The Koi fish can live for 25 to 35 years in captivity. On the other hand, when it comes to the wild, the Koi fish generally live for only 15 to 20 years. The most interesting fact is that a male Koi fish live a longer life in comparison with female Koi fish. Japanese Koi fish live for a longer time because of their outstanding genetics.

Do Koi Die Of Old Age?

I have never seen any Koi fish die of old age. Most of the cases arise when the Koi fish die due to the poor quality of water and sometimes the disorders that make your Koi so weak to live compelling difficulties. You should know that age can not be considered a disease. At an old age, your fish can suffer from serious diseases. But,  it is not believed that Koi died of old age.

How Old Is A 2-Inch Koi Fish?

Generally, 1-year-old koi fish would be around 4-5 inches which means 2 inches koi fish would be in its initial summer age.

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