tetras

Tetras are small, schooling freshwater fish that belong to the family Characidae in the order Characiformes. The term covers hundreds of species across several genera, including popular aquarium forms such as neon tetra, cardinal tetra, glowlight tetra, ember tetra, and rummy-nose tetra. They are native to tropical rivers and streams of South and Central America, where they typically inhabit soft, slow-moving waters with dense vegetation.

Description and behavior: Most tetras have slender, laterally compressed bodies and reach roughly 2–5 cm in length. They are rarely aggressive and rely on schooling behavior for safety, often forming groups of six or more. Coloration varies widely, with iridescent stripes, reds, blues, and yellows that are enhanced by light and diet.

Care in aquariums: Maintain water at about 22–26°C (72–79°F) and pH around 6.0–7.5, with soft to moderately hard water. Provide a well-filtered tank with regular water changes and chasing plants or decorations for cover. Feed a varied omnivorous diet, including high-quality flakes, micro-pellets, and small live or frozen foods such as brine shrimp or daphnia. They prefer stable conditions and can be stressed by sudden changes or aggressive tankmates.

Breeding: Most tetras are egg scatterers. Breeding in home aquariums usually requires a separate tank with fine-leaved plants or spawning mops; remove adults after spawning to protect eggs. Eggs hatch in several days; the fry start on infusoria or very small live foods before transitioning to larger foods.

In the aquarium hobby, tetras are valued for color, peaceful temperament, and schooling behavior. They are not generally endangered, though some wild populations face habitat loss and overcollection. Responsible sourcing and proper care are advised to sustain hobby populations.