Betta care guide
Betta (Betta splendens) — minimum tank 20 L, temperature 24-30 °C, pH 6-7.5. Aggressive top-water species.
Compiled by Aquairi from published sources · Published · Updated
Overview
The Siamese Fighting Fish (Betta splendens) is a labyrinth fish native to Southeast Asia, widely kept for its long fins and intense colour patterns produced through generations of selective breeding. Males are strongly territorial toward conspecifics and must not be housed together.
Taxonomy
- Family: Osphronemidae
- Genus: Betta
- Scientific name: Betta splendens
- Common synonyms: Siamese Fighting Fish
Habitat
Wild populations occur in shallow, slow-moving or stagnant waters of Thailand, Cambodia, Laos, Vietnam, Myanmar and Malaysia, including marshes, floodplains and rice paddies. The labyrinth organ allows the species to breathe atmospheric air and tolerate the low dissolved-oxygen conditions typical of such habitats.
Tank requirements
- Minimum tank volume: 20 L (5.3 US gal)
- Adult size: 5-7 cm
- Temperature: 24-30 °C (75-86 °F)
- pH: 6-7.5
- GH: 3-12 °dGH
- Water flow: none
- Lifespan: 2-5 years
Diet
A carnivore that naturally feeds on zooplankton, small crustaceans, insect larvae (especially mosquito) and surface-fallen insects. In aquaria offer a quality betta pellet supplemented with frozen or live bloodworms, daphnia and brine shrimp. Avoid overfeeding — the stomach is approximately the size of the eye.
Compatibility
Aggressive toward conspecifics and toward other long-finned or brightly coloured species (Guppy, Tiger Barb). A single male may be housed alone or in a peaceful community with calm bottom-dwellers such as Corydoras and Kuhli Loach, Nerite Snails and Otocinclus. Males must never be kept together.
Breeding
Males build bubble nests at the water surface and entice females beneath them; during each embrace approximately 10-40 eggs are released and caught in the nest. The male guards the nest and free-swimming fry alone; remove the female promptly after spawning to prevent injury.
Breeding Betta
Overview
Betta splendens is a bubble-nesting labyrinth fish of intermediate breeding difficulty. The male builds and tends a surface bubble nest, and brood care is carried out solely by the male after spawning. Sexual maturity can be reached as early as 4-5 months.
Sexing
Males are more colourful and develop more extended fins than females, an effect exaggerated in ornamental strains. Morphological differences can usually be told around two months after hatching; females possess an ovipositor tube used for egg delivery.
Breeding Setup
- Temperature: warm, within the species range of 24-30 °C
- Cover: the tightest-fitting cover possible to keep the air warm and humid for the fry's labyrinth-organ development
- Nest sites: floating plants plus tubes or canisters under which the male can build
- Water: relatively shallow and still (no strong flow)
Spawning Behavior & Trigger
The male flares, spreads his fins and builds a bubble nest, initially rejecting the female. When ready, the nuptial female pales and dark bars appear on her flanks. Spawning involves the embrace typical of osphronemids, with the male wrapped around the female; around 10-40 eggs are released during each embrace over a session that can last 1-4 hours. The male transfers sinking eggs to the nest as milt fertilises them in the water.
Egg & Fry Care
After spawning the female must be removed, because she will be chased from the male's territory and may otherwise be killed. The male takes sole responsibility for the nest. Eggs hatch in about 24-48 hours, and the fry remain in the nest a further 3-4 days until the yolk sac is absorbed, the male returning any that fall. Once the fry swim freely the male loses interest. First foods are an infusoria-grade food for the first few days, then microworm and Artemia nauplii.
Common Challenges
Males are highly territorial, so pairings must be supervised and the female removed promptly. The labyrinth organ develops at about three to six weeks, so the warm, humid air layer above the water is essential for fry survival.