Lemon Tetra

The Lemon Tetra is a small characin native to tributaries of the Amazon basin in Brazil, particularly the Tapajós River region. It is named for its pale, lemon-yellow body coloration, most pronounced along the fins. First described in the 1930s, it has become a long-standing favorite in the aquarium hobby for its subtle beauty and peaceful temperament. As a member of the diverse Hyphessobrycon genus, it shares many characteristics with other small Amazonian tetras. The species remains widespread and abundant within its native range and is extensively captive-bred for the ornamental fish trade.

The Lemon Tetra has a moderately deep, laterally compressed body reaching 3.5-4.5 cm.

• Body: Translucent silvery base with a pale lemon-yellow wash, most vivid near the fins
• Anal fin: Bordered in black with a bright yellow edge, a key identifying feature
• Eyes: Upper portion of the iris is red
• Fins: Dorsal fin often shows a black leading edge

It is distinguished from similarly shaped tetras primarily by the distinctive black-and-yellow bordered anal fin, which becomes more vivid and extended in mature males.

Lemon Tetras are native to slow-moving tributaries and blackwater to clearwater streams within the Amazon basin of Brazil, particularly around the Tapajós River drainage. They favor densely vegetated waters with soft, slightly acidic conditions and warm, stable tropical temperatures typical of lowland Amazonian habitats. These environments often include submerged wood, leaf litter, and overhanging riparian plants that provide shelter and shade. As with many Amazonian characins, tannins from decomposing organic matter can tint the water, and the species is well adapted to the nutrient-poor, soft-water conditions characteristic of these tributary systems.

Lemon Tetras are peaceful, social shoaling fish that occupy the middle water column, moving in loose groups while foraging throughout the day. They are omnivorous, feeding on small invertebrates, insect larvae, and plant matter drifting in the water. Males display more vivid yellow coloration and a more extended anal fin during courtship, engaging in gentle chasing behavior to attract females. As egg-scattering spawners, they release adhesive eggs among fine-leaved plants with no parental care following spawning. Their calm schooling behavior and moderate activity level make them a stable, low-conflict presence within mixed-species groups in their native streams.