Lesser Spiny Eel

Macrognathus aculeatus is a compact and adaptable spiny eel distributed widely from India through Southeast Asia into southern China. Its relatively modest maximum size and tolerance for a wide range of water parameters make it one of the most accessible spiny eels for aquarists new to the family.

Like all Mastacembelidae, it is a burrower and requires soft sand substrate to perform its characteristic disappearing act. However, it is less demanding about substrate depth than its larger relatives, and a layer of 5–8 cm is generally sufficient. It is nocturnal and will spend most daylight hours hidden beneath sand, rocks, or decor.

Feeding presents no difficulties: live and frozen bloodworm, tubifex, blackworm, and small earthworm segments are all consumed avidly. This species is peaceful toward tankmates that are not small enough to be swallowed whole, and works well in community aquariums alongside medium barbs, loaches, and catfish.

Water: Soft to moderately hard, pH 6.5–7.5, temperature 22–28°C, GH 3–15, KH 1–8. Tank: Minimum 80 L, fine sand substrate, hiding spots, secure lid. Feeding: Carnivore; bloodworm, tubifex, blackworm, small earthworms, and micro-pellets. Breeding: Seldom bred; soft warm water may encourage spawning behaviour. Compatibility: Peaceful community fish; avoid nano fish and small invertebrates.