Breeding the Asian Knifefish (Notopterus notopterus)

Notopterus notopterus spawns at night in the rainy season, laying egg clumps on submerged plants. A productive species in ponds, it is rarely bred in aquaria.

Overview

The Asian Knifefish or Bronze Featherback (Notopterus notopterus) reaches about 60 cm SL and is found across South and Southeast Asia, in clear streams and the standing or sluggish waters of lakes, floodplains, canals and ponds; it occasionally enters brackish water and is a nocturnal air-breather (FishBase; Wikipedia). It is listed Least Concern by the IUCN and is an important food fish in the region (FishBase; Wikipedia).

Conditioning

FishBase records seasonal migration: the fish colonise floodplains during the rains and return to permanent waters in the dry season, with maturity reached around 15 cm or more. Conditioning thus follows the wet-season cycle of warm, rising water on well-fed adults.

Breeding Setup

Because eggs are laid in small clumps on submerged vegetation (FishBase), a breeding setup must provide dense submerged plants in either stagnant or gently running water, as the species spawns in both.

Spawning Behavior & Trigger

FishBase states that breeding takes place in stagnant or running waters in the rainy season and that spawning occurs at night. A female of 21-25 cm typically produces 1,200-3,000 eggs, which are attached in small clumps to submerged plants.

Egg & Fry Care

The eggs adhere to vegetation after the nocturnal spawn (FishBase). FishBase does not detail subsequent parental behaviour for this species, so claims of guarding or fanning are omitted here; protect the clumps from adult predation in any managed setting.

Common Challenges

Large adult size, the need for a flood-season trigger and night spawning, plus the high egg counts that demand abundant plant cover, make controlled aquarium reproduction difficult and largely confined to pond culture.