Goldfish Breed · Japan (domestic calico)
Shubunkin
Calico speckled pattern on a comet-style body — popular pond fish.
By the WARN Research & Conservation TeamChecked against IUCN Red List & CITES sourcesLast updated
In brief
The Shubunkin goldfish combines calico transparent scales with a comet-style body — mottled blue, red, black and white patches prized in garden ponds. Its defining trait is hardy pond swimming with the same large-volume welfare standards as comets, not indoor bowls.
Shubunkin: At a Glance
| Origin | Japan (domestic calico) |
|---|---|
| Size | Medium (20–30 cm) |
| Typical size | 20–30 cm (8–12 in); calico pattern spreads as fish grows |
| Lifespan | 10–20 years (with excellent care) |
| Scales & finnage | Transparent scales revealing mottled blue-grey base with red, black and white patches — nacreous 'calico' effect. Single long tail like comets; pattern shifts with age and light. |
| Temperament | Active, hardy, colourful |
| Best suited to | Colourful pond setups with other single-tail goldfish — shubunkins need predator-safe pond depth or large filtered aquaria with companions of similar swimming ability. |
History & Origins
Shubunkins developed in Japan in early twentieth century, combining calico genetics with single-tail body types. Bristol shubunkins have fuller tails; London type resembles comets. British pond keepers favour shubunkins for hardiness and colour against green pond backgrounds.
Shubunkin Fun Facts
- Calico colour requires transparent scales — metallic scales hide blue base colour.
- Bristol shubunkin tail is fuller than London type — separate show standards.
- Blue patches often most vivid in young fish, shifting with age.
- Shubunkins tolerate temperate pond life across most of Britain with winter depth.
Shubunkin Common Health Issues
Conditions seen more often in this breed, and how owners and vets help manage them. This is general guidance, not veterinary advice — always speak to your vet.
Poor water quality sensitivity
Calico fish show red streaking on fins when ammonia rises.
Care: Test water and upgrade filtration before cosmetic colour concerns.
Skin infections
Bacterial ulcers follow injury or water quality crashes.
Care: Improve water parameters; aquatic vet antibiotics for deep ulcers.
Predator trauma in ponds
Herons and cats strike colourful pond fish at edges.
Care: Netting, deep water and refuge plants.
Goldfish need ponds, not bowls
Goldfish can live decades in filtered ponds or large aquaria — not tiny bowls. WARN publishes these guides to counter myths that shorten fish lives through poor husbandry.
