Family: Gasteropelecidae
River Hatchetfish — a Gasteropelecidae from South America, gentle, slightly skittish when kept too few. Reaches 3–4.4 cm; schools tightly; never keep below 6. 23–27 °C.
Gasteropelecus sternicla is a Gasteropelecidae from South America. In the wild it prefers warm freshwater streams and lakes; in the aquarium it stays gentle, slightly skittish when kept too few. Plan on 3–4.4 cm of adult fish at 23–27 °C. In a community tank it pairs well with Small Corydoras.
Intermediate difficulty. Gentle, slightly skittish when kept too few; schools tightly; never keep below 6.
Aim for 23–27 °C. Stable temperature matching the species origin; 23–27 °C recorded range.
Expect 3–4.4 cm as an adult, living middle of the water column. A 25 L tank or larger gives it room.
Mid-water omnivore; colour foods keep the red honest. Feed two small meals a day rather than one large one.
Yes, with care. Gentle, slightly skittish when kept too few — pair it with Small Corydoras — Share the lower water peacefully and skip Large or predatory fish — Tetras are snacks.
Comes from South America: warm freshwater streams and lakes. Expect still to gentle current and moderate oxygen levels.
Low escape risk, but a lid is cheap insurance.
In the aquarium: egg-scatterer over fine plants; no parental care. Subtle external differences.