Burmese Spiny Eel

Mastacembelus dayi is a moderately large spiny eel from the river systems of Myanmar and northern Thailand, displaying a subtly attractive reticulated pattern of interlocking dark markings on a pale brown to tan background. It is one of those species that sits just off the beaten path of the spiny eel hobby, less frequently offered than the fire eel or tire track eel but no less rewarding to keep.

In its natural habitat it occupies slow-moving lowland rivers, floodplains, and swamps with soft muddy substrate and abundant organic debris. In the aquarium it requires deep fine sand, strong filtration, and consistent water quality. It is a relatively confident species once established and will often become visible during the evening feeding period.

Earthworms and frozen bloodworm trigger an immediate positive feeding response, and most specimens transition to quality sinking carnivore pellets after acclimatisation. It is peaceful toward tankmates too large to be consumed and works well alongside large barbs, cichlids, and robust catfish in a Southeast Asian predator community.

Water: Soft to moderately hard, pH 6.5–7.5, temperature 22–28°C, GH 3–15, KH 1–8. Tank: Minimum 200 L, deep fine sand, stable decor, strong filtration, sealed lid. Feeding: Carnivore; earthworms, bloodworm, prawns, and sinking carnivore pellets. Breeding: Not documented; assumed egg-scatterer in soft warm conditions. Compatibility: Peaceful with large robust fish; predatory toward small fish.