TankBud

Api api betta

Betta mulyadii

Also known as Betta sp. Api Api, Betta api api, Betta sp. Riau red, Mulyadii betta

FreshwaterFish

Care at a glance

Temperature
75–84°F
24–29°C
pH
4.5–6.0
Adult size
1.1 in
2.8 cm
Minimum tank
8 gal
30 L
Temperament
Mostly peaceful
Social behavior
Solitary
Tankmates
With caution
Swim level
Middle
Difficulty
Difficult
Breeding
Medium
Rarity
Rare
Family
Osphronemidae
Origin
Duri, Riau, Sumatra

Overview

Keep a pair, or a small group in a larger tank, in a quiet species setup or with very small peaceful soft-water fish. It needs very soft, acidic water at 24 to 29 C, pH about 4.5 to 6, and reacts badly to hard water or sudden changes. The male builds a bubble nest under floating leaves and the eggs hatch in a day or two. Feed live and frozen foods small enough for a 3 cm fish, such as baby brine shrimp and daphnia.

In the wild

The Api api betta is known only from one tiny swamp inside an oil palm plantation near Duri in Riau, Sumatra, beside working oil wells, where the original forest is gone and the water is shaded by secondary scrub. It lived there with Betta cf. pugnax and Rasbora einthovenii. Set up a small blackwater tank of 30 liters or more with very soft, acidic, peat-stained water, leaf litter, floating plants and still water.

Good to know

Betta mulyadii is a tiny bubblenester in the Betta coccina group of the family Osphronemidae, described by Ding and colleagues in 2025 and named for Mulyadi Tjoa Hong Tjai, who found it in 2012 and introduced it to the hobby as api-api, Indonesian for flame, after its red body and lance-shaped tail. The type series measured 18.5 to 28.4 mm standard length. Males are uniformly red with faint blue scale flecks and blue-edged fins, which separates them from the blackish B. iaspis, their sister species. The describers propose it be listed as Critically Endangered because the whole known population sits in a swamp of under 5 square kilometres.

Did you know

This fish was a hobby regular for more than a decade under the name api-api before it had a scientific name. The 2025 description finally tied the trade fish to a species, and named it after the collector who had been supplying it since 2012.

Common questions

What size tank does an Api api betta need?

An Api api betta needs at least 8 gal (30 L). It spends most of its time in the middle.

What temperature and pH does an Api api betta need?

An Api api betta is comfortable at 75–84°F (24–29°C) with a pH of 4.5–6.0.

How big does an Api api betta get?

An adult Api api betta reaches about 1.1 in (2.8 cm).

Related species