Starry Night Catfish

Auchenipterus nuchalis is native to the Amazon and Orinoco river systems and is one of the few aquarium catfish that is genuinely active in open water during the day, making it far more visible than most catfish species. Its deep blue-black body spangled with iridescent pale spots creates a startling resemblance to a clear night sky.

Unlike most catfish, Auchenipterus nuchalis is a schooling species in the wild that travels in loose groups through mid-water, feeding on insects and other invertebrates. In captivity it benefits from being kept in groups of four or more and will display confident, open-water behaviour in a sufficiently large tank.

The species is an internal fertiliser — males transfer sperm to females which store it for later use, a remarkable reproductive strategy unique among catfish. It is more delicate than some catfish and benefits from consistently good water quality.

Water: 22–28°C, pH 6.0–7.5, soft to moderately hard; clean, well-filtered water. Tank: Minimum 200L; keep in groups of 4+; mid-water open space essential; some plant cover. Feeding: Omnivore; floating and sinking pellets, frozen daphnia, bloodworm, brine shrimp. Breeding: Internal fertiliser; occasional captive breeding in large groups. Compatibility: Peaceful; excellent with medium South American community fish; keep in groups.