TankBud

Dusky betta

Betta fusca

Also known as Brown betta

FreshwaterFish

Care at a glance

Temperature
72–79°F
22–26°C
pH
5.5–7.5
Adult size
2.8 in
7 cm
Minimum tank
21 gal
80 L
Temperament
Mostly peaceful
Social behavior
Social
Own kind
One male per tank
Tankmates
With caution
Swim level
Middle
Difficulty
Medium
Breeding
Mouthbrooder · Medium
Rarity
Very rare
Family
Osphronemidae
Origin
Medan area, North Sumatra

Overview

The dusky betta is a mostly peaceful wild betta for a roomy, dim tank. It is a good fish once you have some experience.

Did you know

The real dusky betta, Betta fusca, may not exist in the hobby at all. The IBC species program notes that fish imported as fusca are most likely Betta raja or another member of the pugnax group.

Caring for the dusky betta

Keep one male dusky betta with one or two females in a tank of at least 21 gal (80 L). Make it roomy and dim, with sand, driftwood, leaf litter, dense planting and gentle filtration. Keep the lid tight.

Keep the water at 72 to 79°F (22 to 26°C) and a pH of 5.5 to 7.5. It is not fussy about hardness. It takes prepared foods readily, alongside frozen bloodworm, brine shrimp and insects.

Adults are large and boisterous for a wild betta and can rough up small fish. Choose tank mates of a similar size, or none at all. It uses the middle of the water.

The dusky betta is a mouthbrooder, and the male broods for about two weeks before releasing the fry. Breeding is of medium difficulty.

Good to know

Betta fusca belongs to the Betta pugnax group of the family Osphronemidae. Regan described it in 1910 and named it for its dusky look, with a dark band through the eye and dark-edged scales. Tan and Ng redescribed it in 2005 from just two old specimens, the lectotype 59.7 mm standard length. They concluded the species is known only from the type series. FishBase quotes 8.2 cm total length, and aquarium fish sold as fusca reach 10 cm or more. That makes the adult size given here a working figure. The IUCN lists it as Critically Endangered.

In the wild

The dusky betta is a Sumatran fish. Its only confirmed specimens were collected near Medan, in the north of the island, in 1908. Attempts to find it there again have failed. Fish sold under the name come from other parts of Sumatra, such as Pekanbaru. They were taken from pools and flowing forest streams.

Common questions

What size tank does a dusky betta need?

A dusky betta needs at least 21 gal (80 L). It spends most of its time in the middle.

What temperature and pH does a dusky betta need?

A dusky betta is comfortable at 72–79°F (22–26°C) with a pH of 5.5–7.5.

What does a dusky betta eat?

A dusky betta takes prepared foods readily, alongside frozen bloodworm, brine shrimp and insects.

How big does a dusky betta get?

An adult dusky betta reaches about 2.8 in (7 cm).

How does a dusky betta breed?

The dusky betta is a mouthbrooder. The male broods for about two weeks before releasing the fry, and breeding is of medium difficulty.

Related species