Orinoco Knifefish

Sternopygus macrurus is native to the Amazon and Orinoco drainages of South America, inhabiting slow-moving rivers and floodplain lakes with sandy or silty substrates. It is a member of the family Sternopygidae, producing a wave-type electric organ discharge that is one of the stronger signals among the gymnotiform fishes. It has an elongated, eel-like body with a subtle mottled pattern and can grow to a respectable size. Nocturnal and cryptic by nature, it requires plenty of hiding spaces. It is less commonly imported than Black Ghost or Glass Knifefish but is a rewarding specimen for the committed knifefish keeper.

Water: 23-29°C, pH 6.0-7.5, soft to moderately hard; clean water with moderate oxygenation. Tank: Minimum 300L; PVC tubes or hollow logs; fine sand substrate; low to moderate lighting. Feeding: Carnivore; live/frozen bloodworms, earthworms, brine shrimp, tubifex; nocturnal feeder. Breeding: Not documented in home aquaria; seasonal spawner in nature. Compatibility: Generally peaceful; may clash with other knifefish; keep with large dissimilar species.