Betta splendens
Betta (Siamese Fighting Fish)
Bettas are personable, intelligent fish that are routinely mis-sold as low-maintenance. A small heated, cycled and planted aquarium transforms their quality of life.
At a glance
- Scientific name
- Betta splendens
- Family
- Osphronemidae
- Origin
- Shallow waters and rice paddies of Thailand, Cambodia and Vietnam
- Lifespan
- 3–5 years
- Adult size
- 6–7 cm
- Weight
- Under 5 g
- Temperament
- Curious and interactive; males are territorial toward each other
- Activity level
- Moderate
- Social needs
- Solitary males; females can sometimes live in carefully managed groups
- Intelligence
- Learns to recognise people and can be target-trained
- Noise
- Silent
Housing and environment
- Housing
- Minimum 19 litres (5 US gallons), heated, filtered and cycled, with a lid
- Space requirement
- Gentle flow and plenty of broad-leaved plants
- Temperature
- 24–28°C
- Humidity
- Not applicable
- Exercise
- Provided by a planted tank with resting leaves near the surface
- Grooming
- Not applicable; water quality is the equivalent daily care
Diet and feeding
High-protein betta pellets plus frozen or live bloodworm and daphnia
Behaviour and compatibility
Surface air-gulping through the labyrinth organ, flaring, bubble-nest building
- With children
- A good family fish under adult maintenance
- With other animals
- Avoid fin-nipping tankmates and any long-finned fish
- Training difficulty
- Low for simple target and hoop training
Health
- Fin rot
- Velvet
- Swim bladder disorder
- Columnaris
- Dropsy
Aquatic vets exist in many regions; most issues trace to water quality
Special care requirements
Bettas are tropical fish: unheated bowls without filtration are a welfare problem, not a housing option
Before you take one on
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