Slender betta
Betta bellica
Care at a glance
- Temperature
- 77–86°F (25–30°C)
- pH
- 6.0–7.0
- Adult size
- 3.5 in (9 cm)
- Minimum tank
- 20 gal (75 L)
- Temperament
- Mostly peaceful
- Social behavior
- Solitary
- Swim level
- Middle
- Difficulty
- Medium
- Breeding
- No record
- Rarity
- Rare
- Origin
- Sumatra, Malay Peninsula
- Family
- Osphronemidae
Overview
The slender betta is a large, streamlined bubble-nesting betta best kept as a single pair or alone rather than in a group. It is an elongate, active fish that patrols the middle water and can be a strong jumper, so a tightly covered tank is essential. It is generally peaceful but will eat small fish and shrimp, so choose calm, similar-sized tankmates or keep it in a species tank. Feed meaty foods such as bloodworm, brine shrimp, small crickets and a good carnivore dry food. Provide a well-planted, shaded tank of at least 75 liters with plenty of surface cover.
In the wild
Betta bellica is found in Sumatra and the Malay Peninsula, in soft, acidic forest streams and peat-influenced waters shaded by overhanging plants. Recreate that with subdued lighting, driftwood, leaf litter, floating plants and a dark substrate. Keep the temperature warm, between 25 and 30 degrees Celsius, and the pH acidic, from 6.0 to 7.0. Soft, tannin-stained water and a calm surface suit it, and dense planting gives this active, jump-prone fish places to feel secure.
Good to know
A member of the gourami family Osphronemidae, the slender betta reaches around 9 centimeters, making it one of the larger and most streamlined bubble-nesting bettas. The species name bellica means warlike, though it is not an especially aggressive fish. The male builds a bubble nest and guards the eggs and fry. Its breeding difficulty is not formally rated, but it needs soft, acidic water and a compatible, well-conditioned pair to succeed.
Did you know
With its long body and pointed fins, the slender betta looks more like a small pike than a typical fighting fish. The name bellica means warlike, a hangover from a time when nearly every wild Betta was assumed to be a fierce fighter.
Where to buy
Some links may not be the exact species or variety.
…or ask your local fish store.
Appears in
Keeping Slender betta?
Track water tests, reminders and stocking fit.
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