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Oryzias latipes var.
Red and white bicolor medaka like Kohaku koi. Each individual has unique markings. Color fixation is challenging, making selection deeply rewarding.
Kouhaku medaka reproduces the Kohaku koi pattern (red markings on white base) in medaka form, popular as 'swimming miniature koi.' Each individual has completely unique red-white ratio, placement, and pattern shape — no two fish are alike. Fixation rate is low, requiring mass breeding and strict selection of ideally distributed red-white patterns to maintain quality. White containers with top-view observation best reveal the red-white contrast. Carotenoid-containing food helps maintain red coloration. Hardy in 5–30°C, neutral to slightly alkaline water. Strong breeding instinct with spawning mats produces large numbers of offspring for selection.
The Kouhaku Medaka lives 2-3 years.
The Kouhaku Medaka grows to 3-4cm.
Origin
Japan (selectively bred variety)
Lifespan
2-3 years
Size
3-4cm
Temperature
5〜30℃
Medaka pellets, daphnia
Sources: FishBase: Oryzias latipes / Seriously Fish: Oryzias latipes
Selectively bred killifish are trait combinations of body form × body color × pattern × luminescence (internal/external) × scale types (transparent scales) × sparkle × fin morphology and so forth. Published entries include only confirmed traits constituting the given variety, with genetic inheritance patterns provided only for confirmed traits (uncertain cases omitted). Genetic patterns are provided as reference for breeding.
Sources: JMA Japan Medaka Association — Improved Medaka Variety Classification Manual (JA) / Improved Medaka Web Encyclopedia (medakazukan, JA)
A curated selection of notable morphs. Inheritance modes are a breeding-planning guide; actual appearance varies with combos.
Edited & verified by: BreederDirect editorial team
The taxonomic, regulatory, and husbandry data on this page are compiled and verified against the authoritative primary sources below.
Accepted name: Oryzias latipes var. (Temminck & Schlegel, 1846)
Synonyms: Aplocheilus latipes (Temminck & Schlegel, 1846), Poecilia latipes Temminck & Schlegel, 1846, Oryzias latipes latipes (Temminck & Schlegel, 1846)
Authority databases: FishBase · GBIF · Japan Medaka Association — Variety Classification Manual (JA)
Nomenclature follows global taxonomic authority databases.
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White containers show red-white pattern clearly
5-30°C (optimal 20-28°C)
Pattern changes as fish grows
Pattern fixation rate is low — mass breeding and selection needed
Achieving ideal pattern requires multiple generations
Intermediate. This is an intermediate-level species. Some prior experience and knowledge of environmental management are recommended.
The ideal temperature for Kouhaku Medaka is 5〜30℃. Avoid sudden temperature changes and maintain a stable environment.
The average lifespan of Kouhaku Medaka is 2-3 years. With proper care and nutrition, they can live a long and healthy life.
Kouhaku Medaka typically reaches 3-4cm as an adult. Size may vary depending on care conditions and individual genetics.
Kouhaku Medaka feeds on: Medaka pellets, daphnia. Aim for a balanced diet with appropriate feeding frequency.
The price of Kouhaku Medaka varies significantly depending on morph, size, and lineage. Check our market price page for the latest pricing information.
Last updated: August 31, 2026