← All fish
Fish profile · Osphronemidae
Siamese fighting fish
Betta splendens
The Siamese fighting fish is an air-breathing labyrinth fish kept in many selectively bred colours and fin shapes. Males defend territories and should be housed separately; the species naturally occupies shallow, vegetated waters in Southeast Asia.
Last reviewed 26 October 2026 · 6 sources
- Max length
- 6 cm
- IUCN
- VU
- Vulnerable
- Family
- Osphronemidae
- order Perciformes
Category from the IUCN Red List, via GBIF (CC BY 4.0); it may lag the latest Red List assessment.
How big?
Linear scale · hand 18 cm
Up to 6 cm.
How to identify
- Upturned mouth, suited to taking food at the surface.
- Ornamental males often have bright colours and extended fins; wild fish are less showy.
- An extended anal fin runs along the underside of the body.
Habitat
Rice fields and canalsLowland rivers
Shallow rice paddies, ponds and slow streams with dense vegetation.
- Diet
- Small insects and larvae, supplemented in captivity with suitable prepared and frozen foods.
- Native range
- Southeast Asia; captive ornamental strains are widely bred.
Aquarium care
- Minimum tank
- 20 L
- Temperature
- 25–27°C
- pH
- 6.5–7
- Temperament
- Aggressive
More photos
Sources
Last reviewed 26 October 2026