Scherer's hatchetfish

Carnegiella schereri

Also known as Dwarf hatchetfish

FreshwaterFish

Scherer's hatchetfish (Carnegiella schereri) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 73–82°F (23–28°C)
pH: 5.0–7.0
Adult size: 1 in (2.6 cm)
Minimum tank: 14 gal (54 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Top
Difficulty: Medium
Breeding: No record
Rarity: Rare
Origin: Upper Amazon, Peru and Colombia
Family: Gasteropelecidae

Overview

Scherer's hatchetfish is a nano surface fish that must be kept in a school of at least six, and it looks and behaves best in a larger group hanging together under the lid. It stays right at the surface of a modest tank from around 54 liters upward and needs a tight cover, since even a small hatchetfish jumps. It is peaceful and rather delicate, so keep it only with other tiny, gentle fish and avoid anything boisterous that will outcompete it for food or unsettle it. Because it feeds from the surface, offer small floating foods, crushed flake, micro frozen foods, and tiny insects. Stable, clean water matters as much as the group size.

In the wild

This dwarf hatchetfish lives in the upper Amazon of Peru and neighboring Colombia, in slow or still forest waters such as small streams, swamps, and flooded woodland thick with plants. The water is soft and acidic. Match it with warm water from 23 to 28 C and a soft, acidic to neutral pH between about 5.0 and 7.0, kept very stable, as this fish reacts badly to sudden swings. Floating plants and shaded, calm surfaces let it settle and feed in the open. Low mineral content and gentle filtration suit it best.

Good to know

Carnegiella schereri is one of the smallest hatchetfish in the family Gasteropelecidae, reaching only about 2.6 centimeters, sitting in size between the marbled and the pygmy hatchets. Like all Carnegiella it lacks an adipose fin and has a strongly keeled chest packed with the muscles that drive its pectoral fins. Its plain silver body carries faint darker markings along the keel. Breeding is not recorded in aquaria, and wild-caught fish make up the trade.

Did you know

For such a tiny fish it has a surprisingly deep chest, and that wedge is mostly muscle: the pectoral-fin muscles make up a large share of its weight, all of it devoted to its jumping escape.