Checkered barb

The checkered barb (Oliotius oligolepis) is a small, peaceful cyprinid endemic to western central Sumatra, Indonesia, where it inhabits slow-moving streams and lakes including the crater lake Danau Maninjau — its type locality. It reaches a modest 4.0–4.5 cm in standard length and is named for the distinctive black crescent-shaped marks covering each scale, creating a striking checkerboard pattern against a silvery-olive body. The fins display vivid red-orange coloration, particularly intense in dominant males, making this one of the most attractive small barbs available to the aquarist. It is also known as the 'checker barb', 'island barb', and historically as Puntius oligolepis.

Checkered barbs are a schooling species and should be maintained in groups of at least 6–10 specimens. In such numbers they form an active, constantly moving school that adds considerable visual interest to any community tank. They are very peaceful and make ideal residents for the well-researched community aquarium, compatible with similarly-sized cyprinids, tetras, rasboras, and small catfish. In nature they are omnivores feeding primarily on aquatic invertebrates supplemented with smaller amounts of plant material and organic detritus. In the aquarium they are easily fed and accept a wide range of foods, though regular meals of small live and frozen foods such as bloodworm, Daphnia, and Artemia alongside good quality dried flakes and granules ensure the best colour and conditioning.

An aquarium with dimensions of at least 75 × 30 × 30 cm (roughly 68 litres) is recommended for a small school. Choice of décor is not critical, though they show better colouration in a well-decorated set-up with dark substrate, floating or overhanging vegetation, and driftwood roots or branches. Recommended water parameters include a temperature of 18–25°C, pH 5.5–7.5, and hardness 36–215 ppm. They are farmed commercially in enormous numbers and are among the most ubiquitous and affordable species in the aquarium trade. Breeding is straightforward: they are egg-scattering free spawners with no parental care, and the eggs hatch within 24–48 hours.