Java combtail, Belontia hasselti


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Andrew Smith looks at the Honeycomb or Java combtail, Belontia hasselti, which is becoming more easily obtainable in the UK aquarium trade.

Common name: Honeycomb or Java Combtail

Scientific name: Belontia hasselti, Cuvier,1831

Origin: Java, Sumatra, Singapore, Peninsular Malaysia, Kalimantan.

Habitat: Found in slow-moving waters, small streams and blackwater forests.

Size: Males to 20cm/8", females smaller.

Diet: Virtually anything. Will take the larvae of most flies as well as frozen foods in the aquarium. Young raised on flake food will do well on it.

Aquarium care: Can be very aggressive and given its potential size, a larger tank is in order. Even the young can be aggressive, so it is best to either provide a tank with a lot of hiding places, or have a lot of fish in the tank so the aggression is not aimed at one particular fish. Pairs are somewhat secretive and they have a habit of laying flat on their sides for long periods, which looks like the fish has died.

Water conditions: pH on the neutral side or slightly alkaline; lower than pH 6.5 is not really necessary. Keep the hardness relative to the pH. High temperatures are unnecessary: 21-25.5C/70-78F is optimum.

Breeding: Although they are described as a bubble-nesting species, there is every possibility there will be no bubblenest at all when spawning this fish. Males are characterised by the honeycomb pattern in their caudal, and are also much larger than the female.

The colouration takes on a marbling appearance, which is also sometimes what the fish displays in "fright" appearance. At this time the fish become very active. This coincides with a rise in temperature. The pair embrace in what can be described as "labyrinth fashion" with the female approaching the male and butting him in the side.

He in turn curls his body round the female and the embrace occurs. The eggs are yellow in colour and the male keeps these together in a neat cluster.

If you wish to raise a lot of these, then it is probably best to take the young out as they hatch due to the absence of a bubblenest, ie an obvious place for young to be. The eggs hatch after two days and the fry are ready to free swim after a further two days.

They are robust fry that take baby brineshrimp as their first food.

Interesting to note that as with a lot of mouthbrooding Betta species, the female B. hasselti takes up guard duty on the male while he looks after the eggs and young.

Availability: Several Anabantoid Association of Great Britain members have bred and raised them.

Price: Young fish recently sold at about 1.50 each at auction, which is top value for a very long-lived fish

(10-15 years is not unusual).