Tsukiyumi
Tsukiyumi (月弓, "moon bow") is a prized ornamental medaka variety known for the graceful arc of iridescent scale color that curves along its back like a crescent moon's bow. This luminous stripe catches the light beautifully as the fish swims, making each individual a living work of art. Because the pattern and intensity of this arc vary from fish to fish, no two Tsukiyumi look exactly alike. Achieving consistent, well-defined arcs through breeding takes considerable skill, which is why this variety is best suited to experienced keepers rather than beginners.
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- Variety Name
- Lineage
- Actual Photos
- Color Classification
- Body Type
- Scale Type
- Size
- Origin
- Age/Generation
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Tsukiyumi key facts
- Care level
- Advanced
- Lifespan
- 2-3 years
- Size
- 3-4cm
- Temperature
- 5〜30℃
- Diet
- Medaka pellets, daphnia
- Container
- Arc light best visible when viewed from above in black container
- Selection
- Selection of individuals with beautiful arc shape is important
- Water Temperature & Quality
- Tolerates 5-30°C with 20-28°C ideal. Adapts to neutral to slightly alkaline water; keeping it is easy.
- Diet & Feeding
- Feed medaka pellets as the staple plus live foods such as daphnia. Leftovers foul the water, so feed small amounts.
- Breeding
- Low fixation rate requires careful selective breeding
About Tsukiyumi
Tsukiyumi is an advanced-level ornamental medaka prized for the graceful arc of light along its back, reminiscent of a crescent moon — a striking variety for experienced keepers.
7 things to know before welcoming a Tsukiyumi
1Best Suited for Experienced Keepers
Tsukiyumi has quirks in how its arc-shaped color pattern develops and stabilizes, making it a challenging choice for first-time medaka keepers. It's best approached once you've built a foundation in water quality management and basic selective breeding.
2Lifespan: About 2-3 Years
Tsukiyumi typically lives 2 to 3 years. Consistent water changes and careful temperature management help keep them healthy for their full lifespan.
3Adult Size: 3-4cm
Adult Tsukiyumi reach about 3 to 4cm in length. Avoid overcrowding and give them plenty of swimming space, which also supports better development of their signature arc pattern.
4Every Fish's Arc Is Unique
The shape and brightness of the arc-shaped glow along the back vary from fish to fish. It can also look different depending on growth stage and lighting conditions, so it's worth taking time to appreciate how each individual changes.
5Light Enhances the Glow
The arc pattern becomes more vivid under natural sunlight or well-suited lighting. Outdoor keeping or ensuring adequate light exposure will help the glow show at its best.
6Choose Tankmates Carefully
Like other ornamental medaka, Tsukiyumi is peaceful and can be kept with tankmates. That said, keeping them alone or with the same variety makes it easier to appreciate the beauty of their distinctive arc pattern.
7Prepare Your Setup First
Before bringing home a Tsukiyumi, prepare your tank or container, filtration, and temperature control in advance. Since this is a variety best suited to experienced keepers, it helps to have some general medaka-keeping experience first.
Frequently asked questions about Tsukiyumi
- Q.Can beginners keep Tsukiyumi?
- A.Tsukiyumi is considered a variety best suited to experienced keepers. If you're new to medaka, it's a good idea to build your skills with an easier variety first before taking this one on.
- Q.How long do Tsukiyumi live?
- A.They typically live around 2 to 3 years. Regular water changes and careful temperature management make it easier to keep them healthy throughout their lifespan.
- Q.How big do Tsukiyumi grow?
- A.Adults typically reach about 3 to 4cm in length. Individual variation exists, but most stay within this range.
- Q.Does every Tsukiyumi have the same arc pattern?
- A.No — the shape and brightness of the arc vary from fish to fish. Since appearance also shifts with growth stage and lighting, virtually no two individuals look exactly alike.
- Q.How can I bring out the best color in my Tsukiyumi's arc pattern?
- A.Adequate sunlight or suitable lighting helps the arc along the back appear more vivid. Keeping water quality stable and avoiding overcrowding also help maintain good coloration.
Useful tools for Tsukiyumi care
Learn more about Tsukiyumi in the encyclopedia
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Care difficulty, lifespan, size and diet — all basics covered.
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