Siamese fighting fish

Geographic Origin and Biotope: Native to the Chao Phraya and Mekong basins (Thailand, Cambodia, Laos and Vietnam). The wild form, today rare to find pure, exclusively inhabits rice paddies, slow irrigation canals and floodplains rich in submerged vegetation.

Taxonomy and Morphology: Siamese Fighting Fish - Wild Type (Betta splendens). The progenitor of all colorful domestic forms. Unlike the pet store Betta, the wild form has short spade-like fins (natural plakat), a slender, hydrodynamic and exceptionally agile body.

Social Behavior: Males are territorial and will fight to dominate an area, but in nature the clash is rarely fatal because the loser can flee. In a home aquarium, two males will kill each other. Females can be kept in small groups (sororities) in very large tanks.

Coloration and Sexual Dimorphism: Wild "Plakat" coloration: dark brown-red body adorned with rows of iridescent green or blue scales (but without covering the whole body). The fins are red streaked with blue or dark green. Females are brownish with clear horizontal bands and a white ovipositor.

Aquarium Setup: 60 cm (24 inches) tank, very dense planting (Hygrophila, Cryptocoryne), thick layer of floating plants. No water current (air or sponge filter). A lid is essential to keep warm air above the surface (breathes atmospheric air via the labyrinth organ).

Diet and Feeding: Omnivore with carnivorous tendency (insectivorous). Feeds on the surface on insects and mosquito larvae. In the aquarium it accepts any high-quality dry food, but needs frozen bloodworms, daphnia and brine shrimp to avoid intestinal constipation.

Water Quality: Extremely rustic and tolerant. Survives (but does not thrive) even in sub-optimal conditions, which is why it is unfortunately kept in small bowls. For optimal health it requires clean, warm water (26-28°C / 79-82°F) enriched with tannins.

Compatibility and Tankmates: Never two males. Cohabits with slow, peaceful and bottom-dwelling fish (Pangio, Corydoras, Otocinclus, small Rasboras). Livebearers (whose bright colors trigger aggression) and fin-nipping fish like Tetras are not recommended.

Aquarium Reproduction: Bubble nester. The male builds a raft of bubbles at the surface. Mating occurs with an "embrace"; the male recovers the eggs, inserts them into the nest and chases the female away, caring for the offspring alone.

Risks and Diseases: In the wild, the pure wild form is threatened by habitat loss, agricultural pollution (pesticides in rice paddies) and hybridization with carelessly released or escaped domestic specimens.