Aquarist Species: Betta macrostoma 'Marudi' WC
Aquarist: DragonFlyer
Species Profile: Betta macrostoma
Description: Betta native to Borneo. Found in shallow near-stagnant pools and also in fast-flowing waterfalls and quiet tributary pools. It is a paternal mouthbrooder and the male incubates from 12 to 35 days with 21 days being very consistent. It is very tolerant of water chemistry and thrives in almost any type of water however for spawning the water needs to be soft and acidic. Pairs can be housed in a 20 gallon tank, while groups should be housed in a 55 gallon tank or larger. Pairs should be given cover such as caves and plants.
Category: Anabantids
Global Region: Asia
Distribution: Indonesia, Malaysia
CARES Classification: Vulnerable
Aquarist Notes
Photo of aquarist's species:
Collection Point: 'Marudi' (Sarawak, Malaysia)
Genetic Line: F0 Wild Caught
Year Acquired: 2026
I acquired a wild caught pair from BW Aquatics in March, 2026. They arrived in good condition although the male in particular was stressed and needed some medication to come back 100%. The pair actually spawned a few days after shipping which was a huge surprise (and concern, as the male wasn't in top shape). He held for 3 days so failed to carry full term which was fine as I needed him eating medicated food.
Spawning notes:
Species Spawned: Yes
Crazy that they spawned 3 days after receiving them. The species is notorious for males not carrying full term and sure enough after 3 days he was done. Hopefully will see more spawns with some success raising fry.