Beacon Fish (Hemigrammus ocellifer) — 2-2,5cm

Overview

The Head-and-Tail Light Tetra (Hemigrammus ocellifer), also known as the Beacon Fish or Beacon Tetra, is a hardy, peaceful shoaling tetra with distinctive light markings and lively movement for community aquariums. Native to the Amazon and Orinoco river basins of South America, this species (adult size around 3.5 cm) thrives in soft, slightly acidic water and rewards aquarists with active shoaling behaviour, easy care, and striking head-and-tail light markings. Ideal for beginners and experienced keepers alike.

Appearance

Hemigrammus ocellifer displays a slender, laterally compressed body with translucent silver coloration and two distinctive bright spots—one behind the gill cover ("head light") and one at the base of the tail ("tail light")—that glow like tiny beacons, especially under aquarium lighting. The body is accented with subtle iridescent highlights, and a faint dark stripe runs along the midline. Males are slightly more slender than females. The overall appearance is both delicate and eye-catching.

Natural Habitat

This species inhabits slow-flowing rivers, streams, and flooded forest areas across the Amazon and Orinoco river basins in South America. The natural environment is characterised by soft, slightly acidic water, warm temperatures, dense vegetation, submerged wood, and leaf litter. In the wild, Head-and-Tail Light Tetras form large shoals and forage among plants and debris, feeding on small invertebrates, insect larvae, and plant matter.

Aquarium Setup

Recreate a South American biotope with a planted aquarium featuring live plants (such as Amazon swords, Java fern, Vallisneria), driftwood, and open swimming areas. Use a dark sandy or fine gravel substrate to bring out coloration and reduce stress. Ensure stable water chemistry: pH 5.5–7.5, soft to moderately hard water (GH 5–12°), and a temperature of 23–28°C. A minimum of 75 litres is recommended for a proper shoal of at least 6–8 individuals. Provide gentle to moderate filtration, regular water changes, and subdued lighting to reduce stress.

Water Parameters

Head-and-Tail Light Tetras thrive in soft, slightly acidic water typical of South American river systems. Aim for 23–28°C, pH 5.5–7.5, and soft to moderately hard water. Conduct weekly partial water changes (20–30%) to maintain low nitrate levels and replenish essential minerals. Use a high-quality filter rated for the tank volume, and consider adding driftwood or Indian almond leaves to naturally acidify and tannin-stain the water. Monitor parameters closely, as fluctuations can stress these sensitive fish.

Feeding

In the wild, Hemigrammus ocellifer feeds on small invertebrates, insect larvae, and plant matter. In captivity, offer a varied omnivorous diet: high-quality flake or micro-pellet foods supplemented with frozen and live foods such as daphnia, brine shrimp, and bloodworms. Small plant-based components (spirulina-based flakes) are also beneficial. Feed small portions once or twice daily. A balanced diet supports vibrant coloration, healthy growth, and active shoaling behaviour.

Behaviour

This species is peaceful and social, thriving in proper shoals of at least 6–8 individuals. Head-and-Tail Light Tetras are active mid-to-upper water column swimmers that display lively movement and tight shoaling behaviour. They are non-aggressive and make ideal community fish, coexisting peacefully with other small, peaceful species. Watching a shoal move together under aquarium lighting, with their "beacon" spots glowing, is a rewarding sight.

Tank Mates

Suitable companions include other peaceful small tetras (e.g., Neon, Cardinal, Ember), rasboras, Corydoras catfish, Otocinclus, and small peaceful gouramis. Avoid large predatory fish, fin-nipping barbs, aggressive cichlids, large loaches, or any fish large enough to eat them. Careful planning and proper shoal sizes ensure a harmonious South American community.

Breeding

Head-and-Tail Light Tetras are egg-scattering tetras that may spawn over fine-leaved plants or spawning mops in soft, slightly acidic water. Adults should be removed after spawning, as they will eat eggs and fry. Fry require very small live foods such as infusoria or liquid fry food, graduating to newly hatched brine shrimp as they grow. Maintain excellent water quality and stable conditions to support successful breeding.

Why Buy from Tropical Fish Co

Tropical Fish Co is a leading UK specialist in South American tetras for sale, offering healthy, quarantined species including the popular Head-and-Tail Light Tetra. Every fish is carefully selected, acclimated to our expert holding systems, and dispatched with detailed care guidance. Whether you're building your first planted community or adding to an established aquarium, our knowledgeable team is here to support your success. Order online today for fast, reliable delivery and discover why Tropical Fish Co is the trusted choice for premium freshwater fish for sale UK.