Komachi Medaka
Komachi is a strain of red-and-white medaka with normal scales rather than transparent scales. Its main appeal is a clean, bright white body that sets off the vermilion markings, and the contrast is easy to enjoy when you look down into the water. Because a body-glow (taigaiko) fish was used in the original cross, even Komachi bred with Komachi can produce body-glow or glittery (rame) individuals, which adds an element of surprise. Like most medaka, they are gentle swimmers that look lovely in a group. It is a small medaka rated beginner-friendly, so anyone who gets the basics of water preparation and feeding right can keep them comfortably.
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- Actual Photos
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- Body Type
- Scale Type
- Size
- Origin
- Age/Generation
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Komachi Medaka key facts
- Care level
- Beginner-friendly
- Lifespan
- Few reliable data
- Size
- About 3-4 cm (wild medaka reach up to 4 cm SL: FishBase)
- Diet
- Omnivore (floating prepared foods, live foods such as daphnia)
- Container & Tank
- Top view shows the white ground best; fish with a sharp boundary between red and white are the most striking.
- Breeding
- Kohaku patterns vary among siblings; choose breeders with a clean white ground. Shine or lamé fish may appear.
- Tank Mates & Compatibility
- Peaceful and fine with other medaka of similar size. To keep the variety's traits, do not let it breed with other varieties in the same container.
- Diet & Feeding
- Give floating food that is eaten within 3-5 minutes: at least twice a day in summer, once a day in spring and autumn, and little or none outdoors in winter.
- Cautions
- Never release ornamental medaka into rivers, ponds or paddies; hybridisation causes genetic pollution of wild medaka.
About Komachi Medaka
Komachi is a normal-scaled red-and-white medaka with a bright white body that sets off vermilion markings. A small, beginner-friendly medaka.
7 things to know before welcoming a Komachi Medaka
1Beginner-friendly care
Komachi is rated as suitable for beginners. If you cover the basics of medaka keeping, namely settled water, a sensible number of fish, and feeding without leftovers, you can enjoy them without much difficulty. A small container is enough to start, though a larger volume of water generally keeps water quality steadier.
2Body-glow and rame may appear
A body-glow fish was used in the original cross behind Komachi, so body-glow or glittery (rame) individuals can appear even when Komachi are bred together. Not every fish will look the same, so this strain suits people who enjoy that variety. If you want a uniform look, check the listing description and photos carefully.
3White body, vermilion pattern
The charm of Komachi is a white body that makes the vermilion pattern stand out. Since it has normal scales rather than transparent ones, you can also compare its texture with transparent-scaled red-and-white medaka. The contrast is easiest to see from above, and the color of the container and the lighting will change how the fish look.
4Size and container choice
As a small medaka, it can be kept in a small container. Still, leaving plenty of water for the number of fish makes changes in water quality more gradual and easier to manage. Medaka can jump when startled, so leave some space between the water surface and the rim, or use a lid or net.
5Choosing tank mates
Medaka are generally gentle and look lovely swimming in a group. Medaka of similar size and temperament usually get along well, but avoid housing them with very small fry that could fit in a mouth or with large fish. Temperament varies between individuals, so if you see chasing, separate the fish into different containers.
6Acclimation and health checks
When your fish arrive, float the bag on the water to match the temperature, then add tank water little by little to acclimate them. For the first few days, feed lightly and watch for white spots on the body, damaged fins, or changes in how they swim. A problem can have several causes, so if you notice a change, review the water quality and observe the fish in a separate container if needed.
7Lifespan and long-term care
Reliable information on the lifespan of Komachi is limited, so we cannot give a definite number of years. Individuals vary, so the key is to keep up the basics: avoid overcrowding, maintain water quality, and do not leave uneaten food. Keeping simple notes on feeding and water changes helps you notice changes early.
Frequently asked questions about Komachi Medaka
- Q.Can beginners keep Komachi?
- A.Yes, the difficulty level is beginner-friendly. If you follow the basics of medaka keeping, such as preparing the water, keeping a moderate number of fish, and avoiding leftover food, this strain is easy to keep.
- Q.How big do adult Komachi get?
- A.There is little data on the adult size of this variety, and individuals vary. It is a small medaka. Size varies with the individual and the environment, so prepare a container with room to spare.
- Q.How long do Komachi live?
- A.Reliable information on their lifespan is limited, so we cannot state a definite number of years. Individuals vary, so aim to keep them healthy through daily observation and good water quality management.
- Q.Can Komachi parents produce body-glow or rame fish?
- A.Yes, they can. A body-glow fish was used in the original cross, and this is one of the traits of Komachi. However, it will not appear in every offspring.
- Q.Can I keep them with other medaka or fish?
- A.Medaka of similar size and a calm temperament are generally easy to keep together. Avoid housing them with fry small enough to be eaten or with large fish.
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