Wakasagi Medaka – Iridescent Japanese Rice Fish

The Wakasagi Medaka is a refined, improved medaka variety inspired by the Japanese pond smelt. Developed by breeder Yukio Ōba in 2021, this strain features a calming blue body, silver dorsal iridescence, and internal black pigment that offer both beauty and stability. It thrives in both indoor and outdoor environments, making it ideal for dedicated hobbyists and breeders.

Physical Characteristics

• Blue body coloration (青体色): A soft, calming blue that suggests clarity and purity
• External iridescence (体外光): A luminous, silver-like dorsal shine that reflects gently under light
• Internal black pigmentation (体内黒): Subtle internal black tones provide elegant contrast and depth
• Normal scale type (普通鱗): Allows the expression of lamé (sparkling scales) and potential for fin glow
• Neat fins: Cleanly shaped fins that reflect light gracefully, enhancing the medaka’s movement and silhouette

This Wakasagi Medaka line is prized for its balance of clarity, depth, and shine. Its scale structure makes it especially radiant under sunlight or LED lighting. Thanks to its durability and beauty, many breeders choose this variety for ongoing line breeding.

Origin and Development

• Breeder: Mr. Yukio Ōba (大場 幸雄), affiliated with Medaka no Yakata
• Year of Release: 2021
• Lineage: Selectively bred from Seiryū Kiryū Taigaikō (清流きりゅう体外光)
• Key Difference: Developed using normal-scaled offspring to enhance traits like lamé and fin glow
• Concept: Emulates the beauty of Wakasagi with stabilized shine and high fixation rate

🔗 View original strain profile (Japanese): medakazukan.net – ワカサギメダカ

Breeding Notes

• Prioritize fish with strong dorsal shine and clear internal black pigmentation
• Lamé scales and glowing fins should be selected and bred forward
• This line has a relatively high fixation rate, suitable even for intermediate breeders