Kōhaku Taigaikō Medaka – 紅白体外光メダカ

A radiant balance of tradition and brilliance in red, white, and light

Physical Characteristics
The Kōhaku Taigaikō Medaka is a visually stunning variety known for its refined balance of red (vermilion) and white coloration, accompanied by the shimmering external light expression called taigaikō. Reminiscent of the beloved Kōhaku koi, this medaka offers a miniature version of Japanese elegance.

• Body Color: A vibrant contrast of pure white and vivid red-orange, arranged in a balanced pattern across the body
• External Light (Taigaikō): The signature iridescent layer of shine appearing along the back and extending toward the head, produced by light-reflecting iridophores
• Scale Type: Standard (non-transparent), which helps the taigaikō glow stand out against the solid base colors
• Visual Appeal: Striking when viewed from above; the white body reflects light while the vermilion markings and back shine provide dynamic contrast

Origin and Development
While the exact year and breeder of the Kōhaku Taigaikō Medaka remain undocumented, it is widely recognized as a complex and advanced variety to fix. Its name and form pay homage to the classic Kōhaku koi, and it inherits both the beauty and breeding difficulty associated with its namesake.

Unlike tricolor (sanshoku) medaka that often involve the fukurin trait (a silver outer ring on scales), the Kōhaku Taigaikō Medaka lacks this trait, making the development slightly more approachable. However, achieving both vivid red-white balance and strong taigaikō expression requires selective breeding and careful culling over multiple generations.

Breeding Notes

• Even among well-bred lines, the intensity and positioning of the red markings may vary
• The strength of the taigaikō shine is not always visible in fry and often becomes more pronounced as the fish matures
• Maintaining line purity is important for achieving a consistent and high-fixation rate

Conclusion
The Kōhaku Taigaikō Medaka is a refined blend of cultural symbolism and visual artistry. Its red and white coloration reflects traditional Japanese aesthetic values, while the glowing back adds a modern ornamental twist. For breeders and collectors alike, this medaka is both a challenge and a delight—offering elegance, complexity, and unmistakable charm.

Sources / 出典:

• 改良メダカWEB図鑑 – 紅白体外光メダカ
• Photo courtesy of SNR Korea