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Ruby Medaka
IntermediateA beautiful variety with deep red color reminiscent of ruby gemstones. Some transparent-scale types show internal organs.
Difficulty
Intermediate
Temperature
5〜30℃
Lifespan
2-3 years
Size
2-4cm
Diet
Artificial feed, Daphnia
About
Ruby medaka is an improved variety featuring deep red body color reminiscent of a ruby gemstone, standing alongside Youkihi and Kotei as a representative red medaka. Transparent-scale individuals may show internal organs through the body, adding a mystical quality. Black containers are said to best enhance color expression. High-protein, carotenoid- and astaxanthin-rich color-enhancing food maintains and deepens body color. Sunlight exposure further deepens the coloration. Selecting the most intensely red parents for breeding increases the proportion of deeply colored offspring.
Lifespan of the Ruby Medaka
The Ruby Medaka lives 2-3 years.
Size of the Ruby Medaka
The Ruby Medaka grows to 2-4cm.
Temperature & humidity for the Ruby Medaka
The ideal water temperature for the Ruby Medaka is 18〜24℃.
Hardy in 5–30°C, neutral to slightly alkaline water.
Basic Info
Origin
Japan (selectively bred variety)
Lifespan
2-3 years
Size
2-4cm
Temperature
5〜30℃
Care Specifications
- pH
- 7–8
- Hardness (GH)
- 9–19 dGH
- Water Temp.
- 18–24℃
PeacefulGroupBreeding: Easy
Sources: FishBase: Oryzias latipes / Seriously Fish: Oryzias latipes
Morphs (Varieties)
Selectively bred killifish are trait combinations of body form × body color × pattern × luminescence (internal/external) × scale types (transparent scales) × sparkle × fin morphology and so forth. Published entries include only confirmed traits constituting the given variety, with genetic inheritance patterns provided only for confirmed traits (uncertain cases omitted). Genetic patterns are provided as reference for breeding.
RecessiveVisual only with two copies; one copy = het (carrier).
Deep-red body
Other
Transparent scale
Sources: JMA Japan Medaka Association — Improved Medaka Variety Classification Manual (JA) / Improved Medaka Web Encyclopedia (medakazukan, JA)
A curated selection of notable morphs. Inheritance modes are a breeding-planning guide; actual appearance varies with combos.
References & Sources
Edited & verified by: BreederDirect editorial team
The taxonomic, regulatory, and husbandry data on this page are compiled and verified against the authoritative primary sources below.
Taxonomy & Authority
Accepted name: (Temminck & Schlegel, 1846)
Synonyms: Aplocheilus latipes (Temminck & Schlegel, 1846), Poecilia latipes Temminck & Schlegel, 1846, Oryzias latipes latipes (Temminck & Schlegel, 1846)
Authority databases: FishBase · GBIF · Japan Medaka Association — Variety Classification Manual (JA)
Nomenclature follows global taxonomic authority databases.
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