
Source: Wikimedia Commons
Pethia nigrofasciata
A small barb whose breeding males turn purple-red on the head and black behind, and which is pale yellow with dark bars at rest. Endemic to Sri Lankan forest streams and rated Vulnerable by the IUCN.
Pethia nigrofasciata is endemic to forest streams between the Kelani and Nilwala basins of Sri Lanka. FishBase records 6.0cm TL for males and 6.7cm for females, pH 6.0-6.5, 5-12 dH and 22-26C, and places it in cool shaded clear streams over gravel or sand, and in quiet marginal pools, feeding mainly on filamentous algae and detritus. Seriously Fish gives 55mm SL, 20-27C, pH 5.5-7.5, 2-15 dGH and an 80 x 30cm base of about 72 litres, noting that farmed fish are adaptable. Breeding males turn purple-red on the head and black behind. Spawning takes place in shallow water among marginal weeds, where more than a hundred eggs hatch in one or two days and the fry swim free after about a day. Its restricted range has led the IUCN to rate it Vulnerable. It is not listed by CITES.
Source: Wikipedia (CC BY-SA 4.0)
The Black Ruby Barb lives 3-5 years.
The Black Ruby Barb grows to Up to 6.7cm TL.
The ideal temperature for the Black Ruby Barb is 20〜27℃.
Origin
Sri Lanka (Kelani to Nilwala basins)
Lifespan
3-5 years
Size
Sources: FishBase / Seriously Fish
Edited & verified by: BreederDirect editorial team
The taxonomic, regulatory, and husbandry data on this page are compiled and verified against the authoritative primary sources below.
Sources: CITES Appendices (species not listed) / IUCN Red List
Regulations may change. Always verify the latest information with the relevant authorities.
Find listings for this species
Up to 6.7cm TL
Temperature
20〜27℃
Dried, frozen and plant-based foods
Seriously Fish suggests an 80 x 30cm base of about 72 litres. A dark substrate, dense planting and floating plants, driftwood or leaf litter to soften the light bring out its colour. Strong filtration is unnecessary, though it likes some flow.
Seriously Fish gives 20-27C, pH 5.5-7.5 and 2-15 dGH, while FishBase records pH 6.0-6.5, 5-12 dH and 22-26C in the wild. Farmed fish adapt widely, but wild stock prefers acidic, soft water.
Very peaceful and easy to combine with small cyprinids, characins, livebearers, rainbowfish, anabantoids, catfish and loaches. Seriously Fish advises buying at least six to ten, which sharpens the males' colour.
In the wild it is a largely herbivorous omnivore living on filamentous algae and detritus. Use a dried food with plant content as the staple and add frozen bloodworm or Artemia as a supplement.
Widely bred in captivity. It spawns among marginal weeds in shallow water, laying more than a hundred eggs that hatch in one or two days, with the fry free-swimming about a day later. Males are smaller, slimmer and more colourful than females.
Most traded fish are farmed and hardy, but the species itself is a narrowly distributed endemic that the IUCN rates Vulnerable, so captive-bred fish are the better choice over wild-caught stock. It is not listed by CITES.
Beginner. This is a beginner-friendly species. No special equipment or experience is required, and it can be kept successfully with basic care setup.
The ideal temperature for Black Ruby Barb is 20〜27℃. Avoid sudden temperature changes and maintain a stable environment.
The average lifespan of Black Ruby Barb is 3-5 years. With proper care and nutrition, they can live a long and healthy life.
Black Ruby Barb typically reaches Up to 6.7cm TL as an adult. Size may vary depending on care conditions and individual genetics.
Black Ruby Barb feeds on: Dried, frozen and plant-based foods. Aim for a balanced diet with appropriate feeding frequency.
The price of Black Ruby Barb varies significantly depending on morph, size, and lineage. Check our market price page for the latest pricing information.
Last updated: September 17, 2026