Betta mandor

Overview

Betta mandor is a paternal mouthbrooder with dark males, browner females, and paired gill-cover bars. Sensitivity to organic waste and changing conditions makes a mature, stable, sheltered soft-water aquarium essential.

Distribution & habitat

Known collections come from near Mandor and Anjungan in the lower Kapuas drainage of West Kalimantan, Indonesian Borneo. The two origins are often labeled separately to preserve provenance. Historical accounts describe logging disturbance and possible pressure on local populations.

It occupies shaded forest-swamp streams and pools, sometimes in very shallow water. Decomposing vegetation commonly stains the mineral-poor water, with leaves, branches, and roots covering the bed.

Aquarium setup

Provide at least a 60 × 30 cm footprint for a pair and more room for a group. Wood, branches, pots, and pipes make dark retreats. Leaves supply cover and microorganisms; alder cones are another optional botanical addition.

Use subdued light, suitable plants, floating vegetation, and gentle mature sponge filtration. Water should be soft and acidic with little carbonate hardness, potentially requiring a dependable soft-water source. Never introduce fish to a biologically immature system. Secure the cover against jumping while retaining humid air and surface access.

Diet & feeding

Insects, small invertebrates, and zooplankton are likely natural foods. Acclimated fish normally accept dry products, supplemented with water fleas, Artemia, bloodworms, and other live or frozen items. Feed small insects beforehand and avoid excessive portions.

Behaviour & compatibility

Dedicated accommodation is preferable. Large, energetic, or competitive fishes may suppress it, while companions can disrupt breeding. Experiences with multiple pairs or one male and several females vary from limited territorial chasing to sustained bullying. Monitor individuals closely; a compatible pair is a practical starting point for breeding.

Sexual dimorphism

Males show stronger color and longer unpaired fins. Their gill-cover bars are generally better-defined orange-red, compared with gold-yellow bars in females.

Breeding

Repeated embraces produce batches of eggs on the female's anal fin. The male collects them directly and eventually carries the whole brood. Stress or inexperience may cause swallowing or early release, so leaving the female present usually avoids unnecessary catching-related disturbance.

Swimming fry appear after approximately 8–14 days. They can be raised separately or with adults; reports of faster growth beside parents are not guarantees. Maintain warm, humid air over the nursery. Offer microworms and Artemia nauplii in varied small meals two or three times daily, with regular modest water changes.

Notes

Earlier names include Betta sp. ‘Mandor’ and ‘ninja’. It is sometimes sold as the similar Betta foerschi, making collection and breeder provenance valuable when quick visual identification is inconclusive.