How Old Is My Koi In Japaneese?

Tosai, Nisai, Sansai, and Yonsai are crucial classifications in Koi fish, each denoting the fish’s age and growth milestones rather than specific breeds. These categories begin at the fry stage, with Tosai indicating Koi that have completed one year of growth. Nisai follows, designating Koi that are two years old and exhibit further development. Sansai represents three-year-old fish, showcasing more advanced size and coloration. Finally, Yonsai signifies four-year-old Koi, often distinguished by their maturity and enhanced physical characteristics. Understanding these classifications is essential for breeders and enthusiasts aiming to nurture Koi at their respective stages.

First year     Tosai
second        Nisai
third            Sansai
fourth          Yonsai
fifth              Gosai
sixth            Rokusai
seventh       Nanasai
eight            Hassai
ninth            Kyusai
tenth            Jusai
eleventh       Juissai
twelfth          Junisai