Betta unimaculata 

Classification

Order: Perciformes Family: Osphronemidae

Native to parts of the Kajan (upper River Kayan basin) and Howong (River Mahakam basin) river drainages in the Indonesian province of Kalimantan Timur (East Kalimantan), Borneo. These areas are very remote and some accessible only by small boat.

Populations from different localities have been observed to exhibit differences in colouration and patterning and these should never be kept together in aquaria as they will undoubtedly hybridise.

In order to maintain accuracy and preserve pure bloodlines the fish are often labelled with the collection locality by collectors/enthusiasts e.g. Mahakam, Sandakan, etc. The fish from ‘Tawau’ which was initially thought to be B. unimaculata has now been described and named B. ocellata 

Habitat

Has been collected from numerous habitat-types including clear, flowing streams and isolated, elevated pools around headwaters as well as more turbid forested streams.

In flowing headwaters and streams the fish tend to lurk in slow-moving or stagnant pools whereas in the forest streams they’re found among marginal vegetation, leaf litter and submerged tree roots.

One population inhabits the top of a rainforest waterfall (in a place named Bahulak we’ve been unable to locate on a map) with substrate composed of exposed sandstone.

100 – 115 mm.

Aquarium Size

An  aquarium with base measurements of 80 ∗ 30 cm or equivalent is sufficient for a pair.

Maintenance

Can be maintained in a fully-decorated aquarium although many breeders prefer not to use a substrate for ease of maintenance. Driftwood roots and branches can be used and placed such a way that a few shady spots are formed.

If you can’t find driftwood of the desired shape common beech or oak is safe to use if thoroughly dried and stripped of bark. Clay plant pots or lengths of piping can also be included to provide further shelter.

The addition of dried leaf litter, with beech, oak or Ketapang almond leaves all suitable, can further emphasise the natural feel and as well as offering additional cover for the fish brings with it the growth of microbe colonies as decomposition occurs. These can provide a valuable secondary food source for fry and the tannins and other chemicals released by the decaying leaves are also considered beneficial.

Like others in the genus this species seems to do best under fairly dim lighting. You could add aquatic plant species that can survive under such conditions such as Microsorum pteropus, Taxiphyllum barbieri or perhaps some potted Cryptocoryne spp., and a few patches of floating vegetation would be useful to diffuse the light entering the tank.

Filtration need not be too strong, with an air-powered sponge filter set to turn over gently adequate. Keep the tank well-covered and do not fill it to the top as like all Betta spp. it requires occasional access to the layer of humid air that will form above the water surface, and is an excellent jumper.

Water Conditions

Temperature: 21 – 26 °C

pH: 5.0 – 7.5

Hardness: 0 – 179 ppm