Flag Tetra Care Guide
Hyphessobrycon heterorhabdus · Freshwater Fish
What Flag Tetra look like
The Flag Tetra (Hyphessobrycon heterorhabdus) is a diminutive, laterally compressed fish, typically reaching a maximum adult size of approximately 2 inches (5 cm). It exhibits a slender, fusiform body shape that is adorned with three distinct, parallel horizontal stripes: a vibrant red stripe on the dorsal aspect, a lustrous golden stripe in the middle, and a dark stripe along the ventral side, collectively creating a striking tricolor pattern reminiscent of a flag. Sexual dimorphism is subtle, with males generally displaying slightly more intense coloration and a more elongated body shape compared to females, particularly during breeding periods. The species possesses a well-developed lateral line system, which aids in detecting vibrations in the water, and its dentition is characterized by small, conical teeth adapted for an omnivorous diet. The fins are relatively small and delicate, with the dorsal fin being slightly larger and more pronounced, contributing to its agile swimming capabilities. Defensive adaptations include its schooling behavior, which provides safety in numbers, and its ability to quickly dart into dense vegetation to evade predators.
Behavior & temperament
Flag Tetras are social fish that thrive in groups, exhibiting a strong inclination to form schools within their natural habitat. They are primarily pelagic, dwelling in the upper to mid-water column of slow-moving rivers and streams in South America. Their behavior is characterized by a peaceful temperament, making them suitable for community tanks; however, they can display mild territoriality during breeding. Breeding behavior involves egg scattering, where females release eggs among plants, and males fertilize them externally. This species is generally non-aggressive, preferring to interact with their own kind and other peaceful species, although they may exhibit slight competition for food or space when kept in smaller groups.
Diet & feeding
In the wild, Flag Tetras are omnivorous, feeding on a varied diet that includes small invertebrates, plant matter, and detritus. In captivity, they thrive on high-quality flake foods, supplemented with live or frozen foods such as brine shrimp and daphnia, along with vegetable matter to ensure a balanced diet.
Behind the name
Hyphessobrycon (from Greek 'hyphē' meaning 'web' and 'sōbros' meaning 'to have a certain quality') and heterorhabdus (from Greek 'hetero-' meaning 'different' and 'rhabdus' meaning 'rod', referring to the distinctive body pattern).
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Flag Tetra?
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