The Story of the Oldest Koi Fish in History

When people think of koi, they often picture serene ponds, graceful swimming, and vibrant colors. But did you know that koi are also known for their remarkable longevity? One koi fish in particular has become a symbol of endurance and grace — her name was Hanako, and she lived to be over 200 years old.

Who Was Hanako?

Hanako was a beautiful scarlet-colored koi fish who lived in a quiet pond in Japan. She belonged to several generations of the Koshihara family and was passed down as a family treasure.

In 1966, Hanako made headlines when scientists studied the rings on her scales — similar to how tree rings are counted. The results? Hanako was born in 1751 and lived until 1977, making her 226 years old at the time of her passing.

How Was Her Age Proven?

Researchers from Nagoya Women’s College and Laboratory of Animal Science analyzed the scale growth rings using a process called sclerology. They determined the age by counting growth lines, confirming her astonishing lifespan.

Why Did Hanako Live So Long?

Several factors may have contributed to Hanako’s extraordinary life:

• Clean, natural mountain spring water

• Low stress environment

• Minimal predators or threats

• Consistent, careful caretaking by her owners

• Koi kept in ideal conditions — with a healthy pond ecosystem, proper nutrition, and low stress — can often live 25–50 years, and occasionally up to 100+ years.

What Hanako Teaches Us

Hanako’s story is more than just a biological anomaly — it’s a reminder of the harmony between humans and nature. With proper care, koi ponds can become multigenerational legacies, offering joy and peace for decades.

If you're planning to add koi to your pond, remember:

• Invest in good filtration and aeration

• Maintain clean water and balanced parameters

• Provide nutritious food and seasonal care

• Create a safe, naturalistic environment

Let Prestige Help Your Koi Thrive

At Prestige Illumination & Ponds LLC, we build and maintain koi ponds designed for longevity — not just for your fish, but for your entire outdoor lifestyle.

Curtis King

(240) 249-POND (7663) DC & Maryland

(434) 226-POND (7663) Virginia

(540) 272-6866 Main Office

www.prestigepond.com

A well-loved koi is a legacy in motion. Let’s start yours today.