Cuming's barb (Pethia cumingii) care guide

Group
Freshwater fish
Other names
Two-spot barb, Puntius cumingii, Barbus cumingii
Family
Cyprinidae (carps and minnows; subfamily Smiliogastrinae)
Origin
Endemic to the south-western wet zone of Sri Lanka (Bentota and Gin river basins; FishBase gives Kelani to Gin); flowing forest streams over sand, gravel and rock.
Water
freshwater
Maximum size
4.1 cm
Temperature
20–27°C
pH
5.5–7
Hardness
Soft to moderately hard, about 1–12 dGH
Minimum tank
54 litres
Care level
intermediate
Temperament
peaceful

Care

Cuming's barb is a small, peaceful schooling fish that should be kept in a group of six to ten or more. A tank with a base of at least 60 × 30 cm (around 54 litres) is a sensible minimum. It comes from clear, flowing streams through rainforest, over sand, gravel and rocks with leaf litter, so give it a sandy or fine gravel substrate, rounded stones, driftwood, some plants and a gentle to moderate current. Good filtration and regular partial water changes keep the water clean and well oxygenated. Soft, slightly acidic to neutral water suits it best: about 20–27 °C, pH 5.5–7 and hardness roughly 1–12 dGH (18–215 ppm). It is a golden fish with two dark blotches, one behind the head and one near the tail. Males are smaller, slimmer and more colourful than females, especially when spawning. The red-finned fish once treated as a colour form of this species are now a separate species, Pethia reval, from further north in Sri Lanka; fish sold as Cuming's barb may be either, so check the fin colour. It was moved from Puntius to Pethia in 2012. The species has a small natural range and is listed as Endangered by the IUCN (assessed 2020); captive-bred stock is preferable where available. Sources: Seriously Fish (seriouslyfish.com/species/pethia-cumingii/); FishBase (fishbase.se/summary/Pethia-cumingii.html); Wikipedia (en.wikipedia.org/wiki/Pethiacumingii). Checked October 2026.

Diet

An omnivorous forager that eats diatoms, algae, detritus, insects, worms, small crustaceans and zooplankton in the wild. Offer good-quality dried foods with some plant content alongside small live or frozen foods such as bloodworm, Daphnia and Artemia.

Breeding

An egg-scattering free spawner with no parental care, and the adults will eat the eggs. In the wild it spawns with the onset of the rains. Use a separate, dimly lit tank of soft, slightly acidic water with a mesh base, fine-leaved plants or spawning mops, and add a conditioned pair or small group; remove the adults once eggs are seen. Wikipedia mentions around 100 eggs per spawning. Eggs hatch in 24–48 hours and the fry are free-swimming about a day later. Feed infusoria-sized foods first, then microworm and newly hatched brine shrimp.

Compatibility and tank mates

A peaceful fish for a community of similarly sized, calm species such as small tetras, rasboras, livebearers, small rainbowfish, peaceful anabantoids, small catfish and loaches. Keep it in a good-sized group, and avoid boisterous or large fish that would bully or eat it.

Last updated 5 October 2026. Community-edited care guide on Aquatic-Auctions.

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