Pygmy Hatchetfish (Carnegiella myersi) Care Guide
The smallest hatchetfish species, reaching only 2.2 cm. A delicate surface-dwelling fish perfect for mature nano tanks. Translucent body with a faint dark lateral line.
Compiled by Aquairi from published sources · Published · Updated
Overview
Carnegiella myersi is a species in the family Gasteropelecidae. The smallest hatchetfish species, reaching only 2.2 cm. A delicate surface-dwelling fish perfect for mature nano tanks. Translucent body with a faint dark lateral line. Prefers dim lighting with floating plants and calm water conditions.
Taxonomy
- Family: Gasteropelecidae
- Genus: Carnegiella
- Scientific name: Carnegiella myersi
- Other names: Myers' Hatchetfish
- Origin: South America, Peru, Bolivia
Habitat
Native to the upper Amazon basin of Peru, Brazil and Colombia. Inhabits shaded surface layers of slow forest streams. The smallest of the hatchetfishes, it requires soft, warm water and a securely covered tank as it readily jumps.
Tank requirements
- Minimum tank volume: 30 L
- Temperature: 24-28 °C
- pH: 5-7
- GH: 1-8 °dGH
- Water flow: low
- Adult size: 1.5-2.2 cm
- Lifespan: 2-4 years
- Recommended group size: ≥ 8
- Difficulty: intermediate
Diet
Classified as omnivore. Recommended feeding frequency: 2x daily. In captivity, offer a varied diet appropriate to the species — quality prepared foods supplemented with frozen or live items of suitable size.
Compatibility
- Temperament: peaceful
- Swimming level: top
- Compatible tank mates: Ember Tetra, Chili Rasbora, Pygmy Corydoras, Cherry Shrimp
- Avoid with: Betta, Angelfish, Any Large Fish
Breeding
- Breeding strategy: egg-scatterer
- Breeding difficulty: advanced
Pygmy Hatchetfish Breeding Guide
Overview
The pygmy hatchetfish, Carnegiella myersi, is the smallest and most delicate of the nominal hatchetfishes, reaching only about 20-25 mm. Its aquarium reproduction is not recorded; like its relatives it is an egg-scattering surface fish, but no verified captive-breeding account exists.
Sexing
Sexual differences are poorly defined. The only guidance is that females are presumably rounder, especially when viewed from above; there are no dependable colour or fin distinctions.
Breeding Setup
Without a proven method, conditions should mirror the species' soft, acidic origins and surface habits, providing floating cover and very gentle water movement. Reported maintenance parameters are a temperature of 23-26 degrees C, pH 4.0-7.0 and hardness 18-108 ppm.
Common Challenges
The decisive difficulty is the complete absence of documented spawning, leaving no protocol to follow. The fish is very peaceful but small and timid, must be kept in a group of at least six and ideally more, and is an insectivore that takes small floating foods; its delicacy makes both conditioning and any fry-rearing attempt demanding. Until reliable reports appear, breeding remains experimental.