Raikou Medaka
Raikou Medaka is a selectively bred variety combining a vivid orange-red body with the translucent-scale lineage's signature body glow, framed by a black rim outlining each scale. This translucent-scale heritage also gives Raikou its reddish cheeks and fin coloring, lending the fish an elegant, striking look. Bred by Yoshimasa Fukagawa in 2018, Raikou is known for how its markings become more distinct as it matures. Adults reach up to about 4 cm in standard length. Because keeping the coloration and pattern stable takes some experience, Raikou is generally considered suited to intermediate keepers, who can also enjoy its calm, schooling behavior alongside other medaka.
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- Variety Name
- Lineage
- Actual Photos
- Color Classification
- Body Type
- Scale Type
- Size
- Origin
- Age/Generation
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Raikou Medaka key facts
- Care level
- Intermediate
- Lifespan
- 2-3 years
- Size
- Up to about 4cm SL
- Temperature
- 18〜28℃
- Diet
- Prepared medaka food, green water
- Lighting
- The contrast between the scale-edging black and the vermilion reads well from above, while the red cheeks and coloured fins are easier to judge from the side. The Medaka Web Encyclopedia recommends outdoor keeping and suggests shading half the container in summer.
- Diet & Nutrition
- Commercial prepared medaka food is the staple, given in an amount finished within a few minutes. Leftovers decay and foul the water, so adjust the quantity. Green water rich in phytoplankton suits fry rearing.
- Water Temperature & Quality
- Slightly acidic to slightly alkaline water is considered ideal, and the water drifts toward acidic as keeping continues. Around one water change per week is the guideline, and because sudden shifts in temperature or pH cause stress, acclimatise new fish by floating the bag. FishBase records the wild water chemistry of this species as pH 7.0-8.0 and hardness 9-19 dH.
- Tank Mates & Compatibility
- A peaceful schooling fish, normally kept as a group of the same variety. One litre of water per fish is the guideline against overcrowding; overstocking causes poor growth, reduced breeding, oxygen shortage and water fouling.
- Breeding
- Outdoors the spawning season runs from about April to October, once water reaches 18C or above with 12-13 hours of daylight. For year-round indoor breeding, 25-28C water and over 13 hours of lighting are the guideline. Eggs hatch at a cumulative 250 degree-days, about 10 days at 25C.
- Health & Notes
- Black rim is judged on black distributed evenly over the whole body; fish where it breaks up or jumps to separate areas read closer to mottling. A weak black rim may show on only one part of the flank, so select by looking at how the black is spread.
About Raikou Medaka
Raikou Medaka pairs a vivid orange-red body with translucent scales and a black-rimmed pattern. Bred in 2018, this intermediate-level variety develops more distinct markings as it matures.
7 things to know before welcoming a Raikou Medaka
1Best for Intermediate Keepers
Raikou is a selectively bred variety that takes some experience to keep its orange-red body, translucent scales, and black rim looking their best. Since husbandry and selective breeding both affect how the pattern develops, it's best attempted after some basic freshwater fishkeeping experience.
2Watch for Line Dilution
If Raikou crossbreeds with other medaka varieties, the orange-red color and black rim may fade in the next generation. To preserve the line, keep Raikou in a separate tank and breed only with other Raikou.
3Sunlight Enhances the Rim
As with medaka in general, more time in natural sunlight tends to bring out deeper body color and a more defined black rim. Outdoor keeping or a sunny spot can help Raikou's markings develop well.
4Basic Water Quality Care
Like other medaka, translucent-scale varieties are sensitive to sudden changes in water quality. Regular water changes and filter maintenance help keep conditions stable and support overall health.
5Seasonal Temperature Changes
Medaka tolerate a wide range of water temperatures, but outdoor fish slow down as temperatures drop in winter. Set up conditions that avoid freezing and adjust care with the seasons.
6Coloring Changes With Growth
Young Raikou fry don't yet show clear coloring or a defined black rim, which develop as they mature. If choosing fry, keep in mind their final pattern isn't set yet.
7Expect Individual Variation
As a selectively bred variety, individual Raikou vary in the depth of their orange-red color and the evenness of the black rim, even within the same line. Taking time to observe individuals helps you find one you'll be happy with.
Frequently asked questions about Raikou Medaka
- Q.Can beginners keep Raikou Medaka?
- A.Raikou is considered suited to intermediate keepers since maintaining its coloration takes some know-how. It's easier to enjoy once you have some basic freshwater fishkeeping experience.
- Q.How is Raikou different from other translucent-scale medaka like Miyuki?
- A.Raikou combines the body glow typical of translucent-scale medaka with an orange-red body and a black rim outlining each scale. An even, well-defined black rim is considered a hallmark of the variety.
- Q.When does the black rim become clearly visible?
- A.The black rim tends to become more defined as the fish grows. The degree varies by individual, growth stage, and rearing environment.
- Q.Can Raikou be kept with other medaka?
- A.Cohabitation itself is fine, but breeding with other varieties can dilute Raikou's distinctive pattern in future generations. If you want to preserve the line, keep and breed Raikou separately.
- Q.Is Raikou Medaka subject to CITES?
- A.Raikou Medaka is not subject to CITES.
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