According to existing records, information about the largest koi fish in the world is as follows:
I. Current Largest Individual Record
"The Carrot"
Weight: 67 pounds 4 ounces (approx. 30.4 kg)
Length: Over 1 meter
Discovery Location: Caught in 2022 by British angler Andy Hackett in Lac de la Blue Water, France. It lived for over 20 years.
Other Large Koi
A koi raised by British fisherman John weighed 33 jin (approx. 16.5 kg).
The "Gosanke" koi bred by Matsunosuke Koi Farm in Japan reached 1.01 meters in length.
II. Size Limits of Koi
Theoretical Maximum
In ideal environments, koi can grow beyond 1.5 meters in length and exceed 50 kg in weight.
Influencing Factors
Genetics: For example, Matsunosuke bloodlines optimize body shape through hybridization with common carp.
Farming Conditions: Large fish farms provide sufficient space and nutrition.
III. Related Comparisons
Difference from Common Carp
Koi, bred for ornamental purposes, are typically smaller than edible carp (e.g., the Mekong giant carp can reach 300 kg).
Misnomer of "Goldfish"
Some giant koi are mistakenly called goldfish, but they are actually variants within the carp family.
Note: The officially recognized largest koi remains "The Carrot," though larger individuals may exist in wild waters yet to be documented.