Koi fish (Cyprinus carpio) are popular ornamental fish kept around the world. They are long-lived, and Japanese varieties often live more than 50 years. We’ll discover together the oldest koi fish at over 200 years old!
What is the Oldest Koi Fish Ever?
The oldest koi fish ever was named Hanako, and she lived to be 226 years old. The fish died in Higashi Shirakawa Village, in the Kamo District of the Gifu Prefecture in Japan on July 7, 1977.
She was likely born in 1751 during the Edo Period. Her age was determined when scientists harvested some of her scales and studied them for a few years. They counted the growth rings on Hanako’s scales, which work a lot like tree rings when determining age.
Her owner when she died was Dr. Komei Koshihara, who claimed the fish was tame. Hanako was passed down through his family and Koshihara said the fish came when it was called.
The name Hanako means “flower child” in Japanese. She was a scarlet koi, which has an average lifespan of about 45 years. Not only is she the oldest koi, but she’s also one of the oldest vertebrates ever recorded.
Hanako weighed about 16 pounds and was a little over 27 inches long. She lived in a pond with five other koi fish. The other fish were more than 100 years old when they died.

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How Does a Koi Fish Get Over 200 Years Old?
Koi need to experience their winter hibernation to achieve longevity. In their home country of Japan, winters are very cold and water temperatures are frigid. The oldest koi Hanako lived with the seasons by hibernating in the winter and foraging in the summer.
This hibernation state is called torpor and it happens when the water temperature remains below 50 degrees Fahrenheit. You’ll need to make sure that their pond is deep enough that they have water to live in if the top of the water freezes.
A koi’s metabolism slows when in torpor which also slows down cell aging and other factors that affect longevity. Water pH, salt levels, sunlight amounts, vegetation, and water oxygenation all make a difference in the health of koi fish.
Are Koi Aquarium Fish?
No, koi fish are not standard aquarium fish. They are suited for outdoor ponds that are properly maintained. However, they can be kept as aquarium fish when they’re very young until they’re ready for release into a proper body of water.
Any medium-sized koi kept in an aquarium will need at least 50 gallons of water to minimally meet its needs. Every koi that you house with the first will require its own 50 gallons of space. Even these accommodations may not be suitable at all depending on the fish in question.
The growth of koi is stunted if they’re kept in an aquarium long term which is why some believe that they’re lifelong tank fish. However, like goldfish, stunted growth leads to problems that result in early death.
You’ll need an appropriate filter for the amount of water in your tank or pond. This water filter needs to remove enough waste without causing a current. Since koi like still water, the churning of an inappropriate filter may harm your fish.
What Other Pets Outlive Humans?
Humans are expected to live around 75 years which means the pets on this list have the potential to outlive the people who own them. If you’re considering a pet, it’s important to weigh the longevity of a pet with the required long-term commitment.
The following pets may outlive their human owners:
Three of the animals on this list are large birds which may seem surprising since smaller animals usually live shorter lives. That’s because smaller animals usually have higher body temperatures and heart rates than humans which is true of birds. Yet for some reason, a bird’s cells don’t degenerate over time at the same rate as human cells.
Macaw: 70 Years Old
While macaws only last a handful of decades in their natural habitat, some pets become much older. These birds are known to hit 60 to 70 years old in captivity. Some of the oldest macaws on record are more than 100 years old.
Macaws are extremely vocal and interactive. Macaw ownership is a huge time investment and their noise needs to be well tolerated. Without proper mental engagement, macaws become unhealthy and participate in behaviors like feather plucking.

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Cockatoo: 70 Years Old
Like macaws, cockatoos live for a long time. Captive individuals regularly make it up to 70 years of age with exceptional outliers making it past 100 years old.
While any kind of cockatoo can be kept as a pet, the white cockatoo is the most popular because it’s less fussy than the other breeds. These birds need lots of space but they don’t need many toys. They still need mental stimulation so it’s recommended that available toys are rotated frequently.
Cockatoos aren’t cuddly and will start to resent owners that handle them too much. Play is recommended over close contact.
Red Sea Urchin: 200 Years Old
In cold natural environments, this urchin is known to live well over 100 years old without showing signs of aging. Sometimes, they live up to 200 years old. It was previously believed they lasted a little over a decade, but research done in the last few years has shown otherwise.
Red sea urchins are sold as pets for advanced saltwater aquariums. In the wild, they usually die due to predation and rarely make it for an extended period.
African Grey Parrot: 75 Years Old
Kept as a pet for thousands of years, African grey parrots often reach 75 years old. Some individuals last much longer than that.
They’re considered the smartest parrot available and they’re a popular choice because they’re good at emulating speech. Several hours per day need to be devoted to the exercise and play needed to keep an African grey healthy.
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