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Black Ranchu
AdvancedCarassius auratus var.
A ranchu that shines jet black all over. The combination of a solid black chic body color and typical ranchu body shape has unique appeal. Color can change, so environmental management to maintain black coloration is important.
Difficulty
Advanced
Temperature
15〜28℃
Lifespan
8-15 years
Size
10-18cm
Diet
Omnivore (pellets, bloodworms, daphnia)
About
The Black Ranchu combines the celebrated Ranchu body—often called the "king of goldfish"—with a wholly glossy black coloration. It has no dorsal fin and is traditionally enjoyed from above (the Japanese "uwami" viewing culture), where its head wen and rounded, powerful body are best appreciated; the solid black coloration accentuates the Ranchu's curving lines. Black coloration is difficult to fix in goldfish and many individuals fade as they grow or as water quality and temperature shift, so a stable environment is essential to retain the color. The Ranchu already demands attention to body shape and wen condition, and the added challenge of maintaining black color makes this an advanced variety. Keep it in a container of 60 liters or more with clean water, appropriate feeding, and regular water changes. Shallow tubs or basins for top-down viewing are traditionally favored, and the variety receives its own appreciation at shows.
Basic Info
Origin
Japan
Lifespan
8-15 years
Size
10-18cm
Temperature
15〜28℃
Diet
Omnivore (pellets, bloodworms, daphnia)
Care Guide
Housing
Top viewing in shallow round bowls
Temperature
Stable management at 15-28°C
Care Specifications
- pH
- 6–8
- Hardness (GH)
- 5–19 dGH
- Water Temp.
- 18–23℃
PeacefulGroupBreeding: Moderate
Sources: FishBase / Aqueon Goldfish Care Guide
Morphs (Varieties)
金魚品種は体型・尾型・鱗・色の選抜固定(line-bred)。出目・透明鱗(キャリコ)・白子等は単一座。
PolygenicContinuous trait from multiple genes; intensified by selective breeding.
Head growth (wen)
Line-bredEstablished by selective line breeding.
Dorsal-lessEgg-shaped bodyBlack coloration
Sources: Wikipedia - Goldfish (Varieties) / 金魚 - Wikipedia (日本語版・品種)
A curated selection of notable morphs. Inheritance modes are a breeding-planning guide; actual appearance varies with combos.
References & Sources
Edited & verified by: br-choku 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: Carassius auratus var. (Linnaeus, 1758)
Synonyms: Cyprinus auratus Linnaeus, 1758, Carassius auratus auratus (Linnaeus, 1758), Cyprinus thoracatus Valenciennes, 1842, Carassius burgeri Temminck & Schlegel, 1846, Cyprinus chinensis Gronow, 1854
Authority databases: FishBase · GBIF · FishBase: Carassius auratus · GBIF: Carassius auratus · 日本らんちう協会
Nomenclature follows global taxonomic authority databases.
Black Ranchu Listings
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