Betta bellica Care Guide - Tank Setup, Diet & Breeding

Betta bellica is a relatively large, long-bodied wild betta commonly known as the peaceful betta or slender betta. Its elongated shape, iridescent blue-green to bronze colouring and subtle horizontal markings give it a very different appearance from the compact, extravagantly finned Betta splendens seen in most aquarium shops. Mature males may display vivid blue or green tones, particularly when courting or challenging a rival.

This species is a labyrinth fish and can breathe atmospheric air using its specialised labyrinth organ. It is generally more composed than many domestic bettas, although males can still be territorial and individual personalities vary. With their graceful movements and interesting social displays, peaceful bettas are particularly rewarding for aquarists interested in wild forms.

In nature, Betta bellica lives among submerged roots, leaf litter and dense marginal vegetation in quiet forest waters. These habitats are often stained darkly by tannins released from decomposing leaves and wood, while the water may be soft, warm and distinctly acidic. The species is adapted to a secluded environment with abundant cover rather than bright, open water.

Wild populations have a naturally subdued appearance that becomes more expressive during courtship and territorial encounters. Aquarium-bred examples may show stronger blue, green or red highlights, but they retain the slender profile and relatively modest finnage characteristic of the species.

Betta bellica is native to the Malay Peninsula and parts of Sumatra in Southeast Asia, including Malaysia and Indonesia. It inhabits quiet, acidic blackwater environments associated with peat swamps, forest pools and sluggish streams.

A single Betta bellica should have at least a 75-litre aquarium, with a footprint of roughly 90 × 30 cm or larger; a 100-litre tank is preferable for a pair or a carefully planned community. Use a secure lid because the species can jump and needs access to humid air above the water. Provide gentle filtration, subdued lighting, floating plants, dense planting, driftwood, leaf litter and caves or root-like cover over a dark sand or fine smooth substrate. Tannin-rich, soft water and a calm flow recreate its forest blackwater habitat, while open space at the surface allows easy breathing.

Adults can reach approximately 12 cm (4.7 inches) in total length. Males are usually slightly larger and more robust than females, although individual size varies.

Betta bellica is a carnivorous micropredator. Offer a varied diet of high-quality betta or small carnivore pellets supplemented with frozen or live foods such as bloodworm, daphnia, mosquito larvae, brine shrimp and finely chopped prawns. Small terrestrial insects and insect-based foods are also suitable. Feed modest portions and remove uneaten food, as this species is prone to overfeeding in the aquarium.

Peaceful Bettas can live with calm, similarly sized fish that prefer warm, soft and acidic water, including peaceful rasboras, small peaceful barbs, kuhli loaches and quiet small catfish such as Corydoras suited to the same parameters. Avoid fin-nipping species, boisterous tankmates and highly aggressive fish. Males should not be housed together, and keeping males with females requires a spacious, heavily decorated aquarium and close observation; pairs may become aggressive outside breeding activity.

Betta bellica are bubble-nest breeders. Condition a compatible pair with plentiful live or frozen foods, then provide calm, shallow water with floating leaves or other cover beneath which the male can construct his nest. The male embraces the female beneath the nest and places the fertilised eggs into it, where he guards them until they hatch. Remove the female after spawning if she is harassed, and move the male once the fry become free-swimming if necessary. The young require very small first foods such as infusoria or commercially prepared fry food before progressing to baby brine shrimp.

Males are generally larger, more slender and more intensely coloured, with longer and more pointed fins. Females are usually shorter-bodied and fuller through the abdomen, especially when carrying eggs, and may show a visible ovipositor spot when mature.