Black-top mouse catfish

Hassar orestis

Also known as Blacktop doradid

FreshwaterFish

Black-top mouse catfish (Hassar orestis) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 73–82°F (23–28°C)
pH: 6.0–7.5
Adult size: 11.8 in (30 cm)
Minimum tank: 106 gal (400 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Bottom
Difficulty: Medium
Breeding: No record
Rarity: Rare
Origin: Orinoco and Essequibo basins
Family: Doradidae

Overview

This is an active, shoaling armored catfish that only settles when kept in a group, so plan on at least four to six and give them open swimming room down at the bottom. Unlike most talking catfish it stays out in daylight, cruising just above the sand rather than jamming itself into caves. Temperament is peaceful, so it suits similarly sized, calm community fish, though anything small enough to swallow may go missing overnight. Feed sinking pellets, catfish wafers, and frozen foods such as bloodworm and chopped prawn, making sure plenty reaches the floor. A tank of around 400 liters is a sensible starting point, with more length better as the group grows toward full size.

In the wild

Hassar orestis lives in large, flowing rivers of the Orinoco and Essequibo basins, moving over open beds of fine sand in the main channels rather than in still backwaters. Recreate that with a soft sand substrate it can work with its barbels, gentle to moderate current, and clear, well-oxygenated water. Keep it warm at 23-28 C and soft to neutral, around pH 6-7.5, with a little wood or shade at the edges so the group feels secure out in the open.

Good to know

A member of Doradidae, the thorny or talking catfishes, this species reaches about 30 cm and carries the family's bony flank scutes, with a dark blotch over the head and dorsal fin against a silvery body. Like its relatives it can produce audible clicks by locking and grinding its pectoral spines, a sound amplified by the swim bladder. It behaves more like a schooling characin than a typical hidebound doradid. Breeding is not recorded in home aquaria.

Did you know

Most talking catfish spend daylight wedged under wood, but this one shoals in open water by day, swimming in loose formation more like a river minnow than an armored bottom-dweller.

Tank mates

Black-top mouse catfish is a peaceful, schooling species that keeps to the bottom. These picks match on water type, temperature, pH, size and temperament.