Doitsu Koi Care Guide
Doitsu koi are scaleless or partially scaled ornamental carp derived from German mirror carp, kept in outdoor ponds.
Overview
Doitsu koi are an ornamental form of the common carp (Cyprinus carpio var. Doitsu). They are scaleless or only partially scaled, a trait inherited from German mirror and leather carp. Koi are colour varieties of carp kept for decorative purposes in outdoor ponds and water gardens.
Taxonomy
- Family: Cyprinidae
- Genus: Cyprinus
- Scientific name: Cyprinus carpio var. Doitsu
Origin
Systematic koi breeding began in the 1820s in Niigata Prefecture, Japan. The Doitsu lineage traces to German leather and mirror carp: a low-scaled leather carp was sent to Japan from Munich in 1904, and in 1906 a breeder crossed an imported German carp with a Japanese Asagi to create the Shusui variety. These German-derived carp are called Doitsugoi in Japan.
Tank requirements
- Minimum volume: 4000 L (outdoor pond)
- Temperature: 4-26 °C (39-79 °F)
- pH: 7.0-8.5
- GH: 8-20 °dGH
- Lifespan: 25-50 years
Diet
Koi are omnivorous and naturally bottom feeders. They accept prepared foods and plant matter such as peas, lettuce and watermelon, and can be trained to take floating food. Feeding should stop when water temperature drops below about 10 °C.
Compatibility
Koi are peaceful and typically kept with other koi in ponds. They are not suited to indoor aquarium-only setups because of their large adult size (60-90 cm) and high bioload, and they are not plant-safe. Their immune systems weaken below about 10 °C, so cold winters require deeper ponds.