A collection of frequently asked questions about medaka care, covering breeds, breeding, outdoor keeping, and more
The essentials are a tank (or plastic tub / water lily pot), dechlorinator, substrate (akadama soil or aquarium soil), aquatic plants (such as Egeria densa or water hyacinth), and food. For indoor keeping, a filter (box or sponge type) helps stabilize water quality. Outdoors, you can maintain water quality without a filter. Startup costs range from about $20–70 USD.
Medaka adapt to a wide range from 5–30°C (41–86°F), but are most active and breed at 20–28°C (68–82°F). Below 10°C (50°F), activity slows. Below 5°C (41°F), they enter dormancy. In summer, temperatures above 30°C are dangerous — provide shade with reed screens or floating plants.
Himedaka, Youkihi (orange), and Miyuki (metallic shine) medaka are recommended for beginners. Himedaka are the hardiest and most affordable. Youkihi are popular for their beautiful orange color. Miyuki have a stunning metallic sheen, perfect for top-down viewing. Browse actual listings in our Medaka category.
Medaka breed when water temperature exceeds 20°C (68°F) and daylight exceeds 13 hours. They attach eggs to water hyacinth or spawning mops — transfer these to a separate container. At around 25°C (77°F), eggs hatch in about 10 days. Raise fry on green water or powdered fry food. For breeding tips, ask a breeder directly through our Medaka category.
Provide partial shade with reed screens to prevent overheating above 30°C. Install rain guards to avoid sudden pH changes from rainwater. Use netting to protect against predators like birds and dragonfly larvae. Manage stocking density at roughly one fish per liter to avoid overcrowding.
Commercial medaka-specific flakes or pellets are the staple. Feed 1–2 times a day, only what they can eat in 2–3 minutes. Dried daphnia or dried bloodworms as occasional treats can enhance coloration. In winter below 10°C (50°F), reduce or stop feeding.
For indoor keeping, change about 1/3 of the water volume once a week. Outdoor setups with ample plants may only need topping off. Cloudy white water or foul odors indicate water quality problems — change water promptly. For more details, see our User Guide.
Common diseases include ich, cotton wool disease, fin rot, and dropsy. Early-stage infections can be treated with a 0.5% salt bath (5g salt per liter). Focus on water quality management and daily observation for early detection. If you need help, contact us or consult a breeder.
On BreederDirect, you can buy directly from verified medaka breeders. Lineage and variety information is accurate, and without middleman markups, you get fair prices. Post-purchase care advice is available, and the escrow system ensures secure transactions. For details, see our User Guide.
Medaka typically live 2–3 years, with some reaching 4–5 years under proper care. Since breeding is easy, one of their charms is enjoying successive generations. Browse varieties in our Medaka category.