Marine Blue
Marine Blue is a medaka variety prized for its deep, ocean-like blue coloring, and it stands as a flagship among blue-toned strains. Descended from the Mikuni bloodline, it combines translucent scales with a calm, saturated hue that looks especially striking when kept in a group, where the blue tones blend into a gentle gradient. Its temperament is gentle, making it a good fit for mixed tanks with other medaka, and it's considered beginner-friendly to keep. Whether in an outdoor biotope or an indoor aquarium, Marine Blue adapts well to different setups, making it a solid choice for anyone just starting out with medaka.
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- Actual Photos
- Color Classification
- Body Type
- Scale Type
- Size
- Origin
- Age/Generation
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Marine Blue key facts
- Care level
- Beginner-friendly
- Lifespan
- 2-3 years
- Size
- 3-4cm
- Diet
- Medaka pellets
- Container & Tank
- A white container or bright background brings out the blue best. It still stands out in a black container and suits outdoor biotopes well.
- Water Temperature & Quality
- Adapts to 5-30°C and neutral to slightly alkaline water; hardy and easy to keep. Can also be raised in green water.
- Lighting
- Moderate sunlight improves coloring. The blue changes with viewing angle and lighting, so place the container where light reaches it.
- Breeding & Egg-laying
- Breeds readily and spawns actively once a spawning medium is provided. Fixation is relatively high; pairing the bluest individuals yields deeper blue offspring.
- Tank Mates & Compatibility
- Gentle temperament; mixes without trouble and can be kept with other peaceful medaka of similar size.
- Notes
- Some individuals show external light from Miyuki lineage
About Marine Blue
Marine Blue is a striking deep-blue medaka from the Mikuni bloodline. Beginner-friendly and easy to keep, it lives 2-3 years and grows to about 3-4cm.
7 things to know before welcoming a Marine Blue
1Tank & Biotope Setup
At 3-4cm as an adult, Marine Blue is compact enough for either an outdoor biotope or a small indoor tank. Avoid strong water flow, and add aquatic plants for shelter to help them settle in.
2Blue Tones Shine in Groups
Marine Blue's deep blue coloring looks even more striking when several fish are kept together rather than alone. The shade shifts with the angle of light, so it's enjoyable to view from both above and the side.
3A Calm, Easygoing Nature
Marine Blue tends to be calm and generally coexists well with other medaka varieties. That said, be mindful when housing them with much larger or smaller tankmates.
4Beginner-Friendly Care
Marine Blue is rated as beginner-friendly, making it approachable even for first-time medaka keepers. Avoiding sudden shifts in water temperature or quality, combined with routine basic care, is enough to keep them thriving.
5Lifespan & Long-Term Care
With a typical lifespan of around 2-3 years, Marine Blue is a companion you'll care for over several seasons. Adjusting your care routine to seasonal water temperature changes helps support their long-term health.
6Feeding Routine
A commercial medaka pellet feed given in small, frequent portions that fish finish quickly is the basic approach. Keep an eye on quantity and timing to avoid fouling the water.
7Preparing Before You Bring One Home
Letting your tank or biotope water stabilize before bringing your medaka home reduces stress from environmental change. Taking time for a gradual water acclimation process also matters.
Frequently asked questions about Marine Blue
- Q.Can beginners keep Marine Blue medaka?
- A.Yes, Marine Blue is rated as beginner-friendly. With basic water quality management and by avoiding sudden temperature swings, it's an approachable variety even for first-time keepers.
- Q.How long do Marine Blue medaka live?
- A.Marine Blue typically lives around 2-3 years. Consistent water quality management and care adjusted to the season are key to supporting their health.
- Q.How big do Marine Blue medaka get as adults?
- A.Adults reach roughly 3-4cm in length. Being compact, they suit a wide range of setups, from outdoor biotopes to small indoor tanks.
- Q.Is Marine Blue medaka subject to CITES?
- A.No, Marine Blue medaka is not subject to CITES.
- Q.What bloodline does Marine Blue come from?
- A.Marine Blue descends from the Mikuni bloodline and is known as a flagship among blue-toned medaka varieties, distinguished by its deep blue coloring.
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Care difficulty, lifespan, size and diet — all basics covered.
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