Koi can live over a hundred years, but typically, if well cared for, live 20-30 years. The fish will continue to grow throughout its life, and it is those older, larger, most beautiful fish that fetch the sums in the thousands. Koi need a large pond, and that can cost a great deal as well.
How long can koi fish live without food?
During the summer, koi can easily go two weeks without being fed. They will take some small amount of nutrition from bugs, algae, and anything else they can find in the water to eat. Koi can go through the entire winter without eating, and should not be fed if the water temperature is 52 degrees or colder.
Longest living koi fish
Hanako (c. 1751 – 7 July 1977) was a scarlet koi fish owned by several individuals, the last of which being Dr. Komei Koshihara. Her name Hanako is translated as “flower girl” in Japanese. She was reportedly 226 years old at her death. Her age was determined by removing two of her scales and examining them extensively in 1966. At this time, Hanako weighed 7.5 kilograms and was 70 centimeters long. Once the scales were fully analyzed, it was said that she was 215. She is (to date) the longest-lived koi fish ever recorded.Wikipedia