Complete Beginner's Guide to Medaka Keeping

Medaka are hardy freshwater fish well-adapted to Japan's climate, and recent breeding improvements have produced many beautiful varieties. This guide covers medaka keeping basics from scratch.

Required Equipment

• Container: Water lily pots, plastic tubs, aquariums, etc. 10+ liters is recommended
• Substrate: Akadama soil or aqua soil effectively stabilizes water quality
• Plants: Water hyacinth, Anacharis, etc. Also serve as spawning substrate
• Food: Medaka-specific floating flakes. Feed 1-2 times daily, only what's consumed in 2-3 minutes
• Dechlorinator: Essential for neutralizing tap water chlorine

Outdoor vs. Indoor Keeping

Outdoor Keeping Sunlight grows plants and plankton, creating a near-natural environment. Biotope-style layouts are popular. Watch for summer heat (above 35°C) and winter freezing—use reed screens and styrofoam for protection.

Indoor Keeping Easier temperature and water quality control; ideal for side-viewing. Requires a filter (sponge type is optimal) and lighting. Indoor keeping is recommended for closely observing delicate patterns and lame (sparkle) on improved varieties.

Water Preparation Basics

1. Add dechlorinator to tap water per instructions
2. Match temperature before adding to container (within 2°C)
3. Change approximately 1/3 of water weekly
4. Perform immediate water changes if cloudiness or unusual odors appear

Breeding Basics

Medaka begin spawning at water temperatures above 20°C with 13+ hours of daylight. They attach eggs to water hyacinth or commercial spawning mops—transfer eggs (with attachment) to a separate container. At around 25°C, hatching occurs in approximately 10 days. Feed fry powdered fry food or paramecium.

Recommended Varieties

1. Youkihi — Brilliant orange color. Hardy and easy to raise
2. Miyuki — Shimmering body-light along the back. Light intensity varies by grade
3. Tricolor Lame — Red, white, black with scattered sparkle—a luxurious variety
4. Yozakura — Complex beauty of yellow, black, and lame intermingling

Benefits of Purchasing on Bri-Choku

On Bri-Choku, you can purchase directly from medaka breeders.

• Carefully culled specimens: Beautiful individuals hand-selected by breeders
• Clear bloodline information: Directly verify parent fish characteristics and keeping conditions
• No middleman markup: High-quality specimens at fair prices
• Post-purchase support: Consult breeders about care and breeding techniques