Oryzias latipes var.
Improved Youkihi with deeper, more intense crimson. The name 'Koutei' reflects its regal red. Color deepens outdoors.
Koutei (Red Emperor) medaka is a further improved variant of Youkihi featuring an even deeper and more intense crimson-vermilion coloration. The name evokes the overwhelming red presence of an emperor. Multi-generation selective breeding produces lines with particularly excellent coloration approaching true 'deep crimson.' Outdoor sunlight deepens color further; astaxanthin- and carotenoid-rich color-enhancing food maintains and strengthens coloration. Hardy in 5–30°C, neutral to slightly alkaline water. Dark containers and outdoor lotus pots best showcase the deep crimson. Breeding is as easy as Youkihi, with color-quality improvement through selective pairing.
Origin
Japan (selectively bred variety)
Lifespan
1-3 years
Size
3-4cm
Temperature
5〜30℃
Medaka pellets, daphnia
Dark containers make deep red stand out
Sunlight deepens coloration
5-30°C (can overwinter outdoors)
Select and breed deepest-colored individuals
Red color-enhancing feed is effective
Intermediate. This is an intermediate-level species. Some prior experience and knowledge of environmental management are recommended.
The ideal temperature for Koutei Medaka is 5〜30℃. Avoid sudden temperature changes and maintain a stable environment.
The average lifespan of Koutei Medaka is 1-3 years. With proper care and nutrition, they can live a long and healthy life.
Koutei Medaka typically reaches 3-4cm as an adult. Size may vary depending on care conditions and individual genetics.
Koutei Medaka feeds on: Medaka pellets, daphnia. Aim for a balanced diet with appropriate feeding frequency.
The price of Koutei Medaka varies significantly depending on morph, size, and lineage. Check our market price page for the latest pricing information.
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