Koi
Cyprinus rubrofuscus · Cyprinidae
Also known as Nishikigoi, Japanese koi
Intermediate
A pond fish, not an aquarium fish: reaches 60 cm plus and lives for decades.
In short: A koi needs at least 3800 L (1004 US gal), water at 4–28 °C (39–82 °F) and pH 7–8.5. It is peaceful, best kept in groups of 4 or more, and rated intermediate to keep.
- Minimum tank
- 3800 L (1004 US gal)
- Temperature
- 4–28 °C (39–82 °F)
- pH
- 7–8.5
- Adult size
- 60 cm (23.6 in)
- Group size
- 4+
Care requirements
- Minimum tank volume
- 3800 L (1004 US gal)
- Temperature
- 4–28 °C (39–82 °F)
- pH
- 7–8.5
- Hardness
- 8–25 dGH
- Lifespan
- 25–40 years
- Diet
- Omnivore — koi pellets, greens, seasonal wheatgerm food in cold water.
- Care level
- Intermediate
Origin & habitat
- Native region
- Domesticated from East Asian carp
- Water type
- Freshwater
- Biotope
- Large ponds and slow rivers
- Natural conditions
- Pond volume, heavy mechanical and biological filtration, high oxygen.
Behaviour & stocking
- Temperament
- Peaceful
- Minimum group
- 4 fish
- Swims
- All levels
- Good tank mates
- Fancy goldfish in pondsOther koiOrfe
- Avoid
- Indoor aquariumsDelicate plantsSmall fish
Breeding & difficulty
- Breeding difficulty
- Intermediate
- Sexing
- Males are slimmer with breeding tubercles in season.
- Notes
- Spring spawner over brushes; fry are heavily culled.
- Common ailments
- Koi herpesvirusUlcersParasites such as flukes
Will it fit your tank?
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