双斑无须魮 · Two-spotted Barb

Overview

Puntius bimaculatus is a peaceful little shoaling fish whose males can show an attractive reddish flank stripe. Softly lit planting displays it well, but a proper social group matters more than selecting a single exceptionally colorful specimen.

Distribution & habitat

It occurs in Sri Lanka's Nilwala drainage and across southern Indian river systems, including those in Tamil Nadu, Kerala, Karnataka, Andhra Pradesh and Maharashtra. Habitats range from hill streams to quieter middle river reaches, with lowlands generally avoided. Sri Lankan records include mountain streams above 1,500 metres. Reports of fewer brightly colored wild fish suggest possible selective-collection effects, alongside pressures from forest loss and declining water quality.

Aquarium setup

Use a tank at least 60 cm long with dense plants and shade from floating vegetation or branching wood. Strong current is unnecessary. A stream-inspired aquarium is possible, provided it does not subject the fish to torrent-like flow.

Diet & feeding

Its natural foraging combines diatoms, algae and detritus with tiny insects, worms and crustaceans. Offer quality flakes or granules, including a plant- or algae-containing option, and regular live or frozen water fleas, brine shrimp and bloodworm.

Behaviour & compatibility

Maintain six to ten or more together for confidence and stronger male displays. Peaceful small cyprinids, tetras and selected labyrinth or bottom-dwelling fishes may work as companions when size and environmental needs match.

Sexual dimorphism

Females become larger and fuller-bodied; males are more colorful.

Breeding

A trial may use the nursery arrangement recommended for small egg-scattering members of the genus: established water, low light, gentle aeration and fine plants, mops or mesh to protect eggs. Use slightly acidic to neutral water towards the warmer end of the suitable range. Introduce one or two conditioned pairs and remove them when eggs are seen. With this general method, hatching is expected in about 24–48 hours and free swimming roughly a day later. Start with microscopic food, then progress to microworms and brine-shrimp nauplii. These are genus-level expectations rather than a firm species-specific timetable.

Notes

Round dark marks occur at the dorsal- and caudal-fin bases, and the dorsal fin has seven branched rays. The relationship between Indian and Sri Lankan populations remains unresolved. Puntius puckelli is treated as a synonym and should not simply be applied as a separate species name to Indian fish.