Bottlenose Catfish Care Guide - Aquarium Setup, Diet & Breeding

The Bottlenose Catfish is a distinctive South American driftwood catfish with an elongated body, a broad, flattened head and a noticeably rounded, projecting snout. Its marbled brown, grey and cream patterning helps it blend into the shadowed river environments where it spends much of its time. Long barbels around the mouth assist with locating food in dark or turbid water.

Ageneiosus marmoratus is native to tropical South America, occurring in freshwater river systems of the Amazon and neighbouring northern South American drainage basins. It is associated with warm, flowing waters, floodplain habitats and areas containing submerged wood and other cover.

Plan on at least 240 litres for one adult, with a tank measuring approximately 120 cm long by 45 cm wide or larger; more space is needed for multiple adults or mixed communities. Use a soft sand or smooth fine-gravel substrate, sturdy driftwood and subdued lighting, leaving open swimming space as well as shaded retreats. The aquarium should have a secure cover, efficient filtration and good oxygenation, while avoiding sharp decor that could damage the catfish's delicate barbels.

Adults reach approximately 25 cm (10 in) in length. Females may grow slightly larger and heavier-bodied than males.

This opportunistic predator accepts meaty foods such as sinking carnivore pellets, chopped prawns, mussel, earthworms and other suitably sized frozen or fresh foods. Offer food after the aquarium lights dim, when it is naturally most active. A varied diet is preferable to relying on feeder fish, which can introduce disease and provide poor nutrition.

Suitable companions include robust, similarly sized South American fish such as large peaceful cichlids, silver dollars, larger characins and substantial plecos, provided the aquarium is spacious. Avoid small tetras, livebearer fry, shrimp and other fish that can fit into its mouth, as this nocturnal predator may consume them. It should also not be housed with highly aggressive species or delicate bottom dwellers that would be outcompeted or harassed.

Bottlenose Catfish are rarely bred in home aquaria. In the wild, reproduction involves internal fertilisation: mature males develop a modified anal fin and associated reproductive structures used to transfer sperm to the female. The female subsequently releases adhesive eggs, which are fertilised and left to develop without parental care. Successful aquarium breeding would require a large, mature system, excellent water quality and a compatible adult pair, but reliable captive-breeding methods are not well established.

Females are generally larger and more robust than males. Mature males develop a modified anal fin and specialised reproductive structures, although these differences can be difficult to identify in young fish or from a casual view.