Black Ruby Barb Care Guide
Pethia nigrofasciata is a peaceful schooling barb endemic to Sri Lanka; spawning males turn a deep ruby-red.
Compiled by Aquairi from published sources · Published · Updated
Overview
Pethia nigrofasciata, the black ruby barb, is a small cyprinid described by Günther in 1868. It is endemic to Sri Lanka and is well known in the aquarium hobby for the striking colour change of mature males, whose body turns a dark ruby-red during spawning.
Taxonomy
- Family: Cyprinidae
- Genus: Pethia
- Scientific name: Pethia nigrofasciata
- Common synonyms: Barbus nigrofasciatus, Puntius nigrofasciatus
Habitat
The species is restricted to the Kelani and Nilwala river basins in the southwestern wet zone of Sri Lanka. This tropical rainforest region receives 2,000-3,000 mm of annual rainfall and has fairly constant water temperatures of about 25-27 °C. The fish inhabits forested, shaded streams with sandy or gravelly substrates.
Tank requirements
- Minimum tank volume: 100 L (about 26 gal)
- Temperature: 22-26 °C (72-79 °F)
- pH: 6.0-7.5
- GH: 5-18 °dGH
- School size: at least 6-10 individuals
- Lifespan: 4-6 years
A heavily planted setup with a dark substrate, floating plants, driftwood roots and leaf litter suits the species.
Diet
Wild populations forage on diatoms, algae, detritus and small invertebrates. In the aquarium the black ruby barb is an omnivore that accepts good-quality dried flakes and granules alongside small live and frozen foods such as bloodworm, Daphnia and Artemia.
Compatibility
Pethia nigrofasciata is generally very peaceful and is a schooling species by nature, so at least six to ten specimens should be kept together. A larger group encourages natural behaviour and helps males develop their best colour. It suits a peaceful community of similarly sized fish.
Breeding
The black ruby barb is an egg-scattering free spawner that provides no parental care. Spawning males develop a reddish-purple head and anterior body. Females scatter more than 100 eggs among fine-leaved plants in shallow water, and the eggs hatch within about 24-48 hours.
Conservation status
Wikipedia lists the species as Vulnerable on the IUCN Red List, with collection for the aquarium trade cited as a pressure; export of wild specimens from Sri Lanka is currently prohibited.
Black Ruby Barb (Pethia nigrofasciata) Breeding Guide
Overview
Pethia nigrofasciata is a barb endemic to Sri Lanka, restricted to forest streams of the Kelani and Nilwala basins in the island's southwestern wet zone. It reaches about 50-55 mm standard length and is an egg-scattering spawner with no parental care that has been bred successfully in captivity.
Sexing
Adult males are noticeably smaller, slimmer and more colourful than females, especially during the spawning season, when the colour pattern darkens and the head and front of the body become reddish-purple. Females are plainer and rounder-bellied.
Conditioning
Condition adults together on a varied diet until males show their nuptial colour and females are full of roe. Wild-type fish do best in soft, slightly acidic water; farm-raised stock is more adaptable.
Breeding Setup
Place a well-conditioned pair in a very dimly lit spawning tank with a mesh or plant base so eggs can fall through while the adults cannot reach them. FishBase notes spawning occurs in shallow water among marginal weeds, so fine-leaved plants suit this species well.
Spawning Behavior & Trigger
The pair scatters eggs over the spawning medium; clutches can exceed 100 eggs. Warm, soft water and good conditioning bring the fish into spawning condition.
Egg & Fry Care
The adults will probably eat the eggs given the chance and should be removed as soon as any are noticed. Eggs hatch in roughly 1-2 days, with fry free-swimming around 24 hours later. Start the fry on infusoria-grade food until they can accept microworm or Artemia nauplii.
Common Challenges
Egg predation is the main risk and is solved by an egg-trap base and prompt removal of adults. Wild-collected stock may be reluctant to spawn unless the soft, acidic water of its native streams is provided.