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Goldfish

The goldfish (*Carassius auratus*) is a domesticated freshwater fish in the carp family, Cyprinidae, native to East Asia.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 26, 2026|2 min read| Fact-checked

The goldfish (*Carassius auratus*) is a domesticated freshwater fish in the carp family, Cyprinidae, native to East Asia. It is widely kept as an ornamental aquarium and pond fish, and released fish have become invasive in some regions. Goldfish were selectively bred in China more than 1,000 years ago and now exist in many varieties.

Taxonomy and origin

Goldfish (*Carassius auratus*) are a species of freshwater carp in the family Cyprinidae. They originated in East Asia, particularly China, where domestication and selective breeding for colour and form began more than 1,000 years ago.

Description and varieties

Goldfish exhibit wide variation in colour, size, body shape, and fin structure as a result of centuries of selective breeding. Many named breeds exist, including common and fancy varieties. Goldfish are omnivores.

Behaviour and habitat

Goldfish are freshwater fish commonly kept in aquariums and ponds. Their adaptability to a range of conditions contributes to their success as invasive species when released into the wild.

Human use and ecological impact

Goldfish have long been valued as ornamental pets and water-garden fish. In some regions, escaped or released goldfish can establish wild populations and become invasive, affecting native ecosystems. In Canada, released goldfish can become invasive in local waters. The species is listed as Least Concern on the conservation status.

Key facts

  • Goldfish are a domesticated form of a freshwater carp native to East Asia.
  • Selective breeding in China began more than 1,000 years ago.
  • Goldfish are among the most popular aquarium and pond fish.
  • Released goldfish can become invasive in some regions.
  • Goldfish show wide variation in colour, size, body shape, and fin structure.
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Canadian context

Goldfish are kept as pets in Canada, but released fish can become invasive in Canadian waters. Canadian readers may also encounter local restrictions or guidance on releasing aquatic pets, especially where wild populations are established.

Frequently asked questions

What is a goldfish?
A goldfish is a domesticated freshwater fish, *Carassius auratus*, kept mainly as an ornamental aquarium or pond fish.
Where do goldfish come from?
Goldfish were domesticated in China from East Asian carp more than 1,000 years ago.
Are goldfish invasive?
They can be invasive when released into the wild, where they may establish self-sustaining populations in some regions.
What family do goldfish belong to?
Goldfish belong to the carp family, Cyprinidae.
Why are goldfish different shapes and colours?
Centuries of selective breeding produced many varieties with different colours, body shapes, and fin types.

References

  1. Encyclopaedia Britannicahttps://www.britannica.com/animal/goldfish
    Supports: Goldfish are *Carassius auratus*, ornamental aquarium and pond fish, native to East Asia.
  2. National Geographichttps://www.nationalgeographic.com/animals/fish/facts/goldfish
    Supports: Scientific name, diet, typical lifespan, size, and domestication as an ornamental fish.
  3. Encyclopedia.comhttps://www.encyclopedia.com/plants-and-animals/animals/vertebrate-zoology/goldfish
    Supports: Goldfish are freshwater carp from China, domesticated about 1,000 years ago, with many colour forms.
  4. Animal Diversity Webhttps://www.animaldiversity.org/accounts/Carassius_auratus/
    Supports: Native range in eastern Asia, habitat, longevity, and invasive status in some regions.
  5. Minnesota Department of Natural Resourceshttps://www.dnr.state.mn.us/invasives/aquaticanimals/goldfish.html
    Supports: Goldfish are freshwater carp, omnivorous, variable in appearance, and can be invasive when released.
  6. Pennsylvania Sea Granthttps://seagrant.psu.edu/resources/resource-item/goldfish-ais-fact-sheet/
    Supports: Goldfish as an aquatic invasive species in North America and their ornamental introduction history.