Medaka (Japanese ricefish, *Oryzias latipes*) is a small ornamental fish that has been loved in Japan and East Asia for centuries. They come in many colors and body types, and their beauty especially shines under natural sunlight.

We offer both. Some strains are imported from trusted breeders in Japan, while others are homebred here in North Carolina.

No. We only sell live fish to ensure quality, transparency, and visible traits. Eggs can be unpredictable and don’t allow proper sexing or grading.

Yes, when available. We offer males, females, and confirmed breeding pairs. However, longfin and swallow-tail types may be harder to sex accurately, especially at a young age.

If a fish arrives dead, send us a video within 2 hours showing the fish inside the sealed bag and again after opening. We’ll issue a full refund for that fish. For full DOA policy and instructions, please visit our DOA & Shipping Guide page.

It depends on your USDA Hardiness Zone. Medaka thrive outdoors from spring to fall, but winter survival varies by climate. Here’s a guide:

• Zones 9–11 (Warm climates): Outdoors year-round. Provide shade and aeration in summer.
• Zones 7–8 (Mild climates): Outdoors year-round with precautions. Use tubs 18–24" deep, insulate with foam or straw, and provide plant/leaf cover.
• Zones 5–6 (Cold climates): Outdoors possible with deep tubs (24–30"), insulation, and a pond de-icer. Many keepers bring fish indoors for winter.
• Zones 3–4 (Harsh winters): Too cold for outdoor overwintering. Move fish indoors or to a heated greenhouse/garage.

General tip: If water freezes solid, fish cannot survive. Depth and insulation make the difference.

Yes. Medaka adapt well to indoor aquariums or tubs. If natural sunlight is limited, a full-spectrum LED light helps maintain their health and vibrant colors.

• pH: Generally near 7.0 (6.5–8.0 acceptable)
• Temperature: 70–90°F (21–32°C) in summer, can adapt to lows near 20°F (-6°C) in Zone 8a winters
• Hardness: Natural GH/KH, not artificially altered
• Ammonia/Nitrite: 0 ppm — all systems cycled and naturally planted

Maintain stable water conditions, provide 12–14 hours of light daily, and offer live or high-quality food. Use spawning mops or floating plants. It helps to start with more than one pair or trio to improve success.

Culling means carefully selecting which fish to keep for breeding and which not to use. It is one of the most important practices in maintaining high-quality medaka.

Even if fish originally come from top-quality Japanese breeders, their traits can decline quickly without consistent selection. Over time, colors may fade, body shapes may lose balance, and unique features of the strain may weaken.

By culling, breeders preserve the lineage, traits, and reputation of each strain. Without it, quality can collapse within just a few generations.

For anyone planning to breed and sell medaka, setting clear selection standards is strongly recommended to ensure the strain remains healthy, stable, and true to type.

Normal is the standard body shape. Hikari types have reflective bodies and different fin structure. Daruma are short-bodied, rounder, and typically grow smaller.

Yes. Medaka thrive in glass aquariums. Adding sand, gravel, and aquatic plants helps create stability, improves water quality, and provides a natural-looking environment.

However, some strains are sensitive to background reaction. In those cases, fish may appear paler or change color when kept in clear glass aquariums. A darker background or added plants can help maintain vibrant coloration.

Yes. They coexist peacefully with shrimp like cherry shrimp or Amano shrimp (note: tiny baby shrimp may be eaten). They also get along with other peaceful small fish, but avoid aggressive or fin-nipping species.

About 2 gallons (~7.5 L) per adult medaka is recommended. Experienced keepers may keep 1 gallon (~3.8 L) per fish, but 2 gallons is safer.

Example: A 20-gallon (~75 L) tub = 10–12 adults comfortably.

Yes. To protect fry:

• Use separate fry tubs
• Add spawning mops or plants
• Keep adults well-fed

Indoors: Keep water 65–75°F (18–24°C), stable quality, light feeding. Use a heater if needed.

Outdoors: Ensure tubs don’t freeze solid. Gentle aeration, deeper water, and dried leaves (almond/persimmon) provide cover and tannins. Avoid disturbing water and overfeeding — medaka rest naturally.

Spring tip: Resume water changes gradually and monitor condition closely, as many losses occur during seasonal transitions.

• Medaka-specific dry foods (powder, granules, floating type)
• Live foods (baby brine shrimp, daphnia, microworms)
• Natural insects/plankton in outdoor tubs

We recommend Hikari Medaka Feed for best growth and coloration.

On average, 1–2 years with proper care. Some live longer in well-maintained environments.

Yes, they can. Always cover aquariums or tubs with a lid or net to prevent jumping accidents.

They are imported live fish. Importing requires permits, inspections, and coordination. Most come from Japanese breeders who dedicate full time to raising them, reflected in cost. Hobbyist-bred fish are usually cheaper, but usually not comparable in quality or lineage.

Prices depend on availability, strain rarity, and breeding difficulty. Seasonal conditions also matter — prices are generally lower in summer when breeding is easier, and higher in winter.

Yes. If fish health declines before shipping, we may cancel. Options include:

• Holding until fish recover
• Switching to a similar available strain
• Refund

This ensures only healthy medaka are shipped.

Yes. Leave a note with your preferred delivery window at checkout. ⚠️ We do not ship to PO Boxes.

Hawaii: Requires import permit. We issue a manual invoice after confirmation. Excluded from flat-rate shipping.

Alaska: Excluded from flat-rate shipping, handled manually with adjusted costs.