Family: Characidae
Featherfin tetra, Flag tetra — a Characidae from South America. Reaches 4–5.8 cm; keep at 23–28 °C.
Hemigrammus unilineatus is a Characidae from South America. In the wild it prefers blackwater streams and flooded forest; in the aquarium it stays mostly peaceful. Plan on 4–5.8 cm of adult fish at 23–28 °C. Related profiles: Hemigrammus bleheri, Hemigrammus ocellifer, Hemigrammus rhodostomus.
Difficulty: moderate. Mostly peaceful; larger species predatory. Strong shoalers; keep in groups of 8 or more.
Aim for 23–28 °C. Heater for stable tropical warmth; 23–28 °C recorded range.
Expect 4–5.8 cm as an adult, living bottom-dwelling. A 40 L tank or larger gives it room.
Omnivore with carnivorous tilt. Vary the menu — quality flakes or pellets plus frozen or live foods.
Mostly peaceful; larger species predatory; strong shoalers; keep in groups of 8 or more. Good company: Similar-sized peaceful community fish — Similar size and water needs. Keep away from Much smaller fish — May outcompete or bully tiny tankmates.
Native to South America, where it lives in blackwater streams and flooded forest. Still to gentle current; Moderate.
Jumping is not a known issue; cover the tank anyway during water changes.
Egg-scatterer among fine plants. Subtle; females fuller-bodied.