Bryan McAllister’s personal reference notebook
July 30, 2026Short & citedBlog
Civic Viewpoint.
A quiet encyclopedia with a personal desk
Kept by Bryan McAllister — short guides, clear facts, and the Canadian angle when it matters.
Field Notes • Fish

Betta fish

Betta fish are small freshwater fish in the genus Betta, best known in aquariums through the species Betta splendens, also called the Siamese fighting fish.

Updated July 30, 20261 min readCited sources

Betta fish are small freshwater fish in the genus Betta, best known through the species Betta splendens, also called the Siamese fighting fish. They are native to Southeast Asia and popular as aquarium pets.

What it is

Betta fish are small, colourful freshwater fish with flowing fins, especially in selectively bred aquarium varieties. The genus Betta includes more than 70 species, but the common pet-store betta is Betta splendens. They are known for territorial behaviour, particularly in males, which fight other males.

Key details

Wild bettas live in shallow freshwater habitats like rice paddies, marshes, and slow streams across Southeast Asia, including Thailand, Cambodia, Laos, and Vietnam. In captivity, they typically live 2 to 5 years and need clean water, space, and a suitable omnivorous diet. They are among the oldest domesticated fish.

Why it matters

Betta fish are widely sold and kept as aquarium pets in Canada, where they are a common freshwater species in the pet trade. Understanding their care needs and natural behaviour helps ensure they thrive in captivity.

In short

  • Betta splendens is the most common pet betta, also called Siamese fighting fish.
  • Native to shallow waters in Southeast Asia, including Thailand.
  • Males are territorial and may fight other males.
  • In captivity, they live about 2 to 5 years.
Canadian angle

Betta fish are widely sold and kept as aquarium pets in Canada, where they are a common freshwater species in the pet trade.

Quick questions

What is a betta fish?
A betta fish is a small freshwater fish in the genus Betta, most commonly referring to Betta splendens, the Siamese fighting fish.
How long do betta fish live?
In captivity, betta fish usually live about two to five years, though some can live longer with excellent care.
Why are they called Siamese fighting fish?
The name refers to their origin in Thailand, formerly Siam, and to the territorial fighting behaviour shown especially by males.

Sources

  1. National Geographic — https://www.nationalgeographic.com/animals/fish/facts/betta-fish
    Supports: Scientific name, size, lifespan, native range, habitat, and vulnerability status.
  2. Live Science — https://www.livescience.com/betta-fish.html
    Supports: Number of betta species, native habitat, size, and conservation status.
  3. World Animal Protection — https://www.worldanimalprotection.us/latest/blogs/betta-fish-10-facts-about-siamese-fighting-fish/
    Supports: Native range, lifespan in captivity, and general diet information.
  4. PetMD — https://www.petmd.com/fish/care/betta-fish-facts
    Supports: Captive lifespan, care requirements, and territorial behaviour.