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Black Ruby Barb

Puntius nigrofasciatus

Native to southern Sri Lanka, inhabiting slow-flowing, shaded forest streams with gravel beds covered in leaves. Prefers cool and clear waters.

Family
Cyprinidae
Origin
Asia: shaded forest streams of southern Sri Lanka.
Origin
Extra-Amazon South AmericaSouth and Southeast Asia
Tank use
Used in 0 tanks

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Species challenges
Water Temperature

20 °C - 26 °C

pH Value

6 - 7

Water type

Freshwater

Tank level

Metà

Adult size

6 cm

Species description

Geographical Origin and Habitat: Native to southern Sri Lanka, inhabiting slow-flowing, shaded forest streams with gravel beds covered in leaves. Prefers cool and clear waters.

Taxonomy and Morphology: Also known scientifically as Pethia nigrofasciata, it belongs to the Cyprinidae family. It features a deep-bodied, laterally compressed shape, growing to 6.0 cm.

Social Behavior: An active yet peaceful schooling species. Must be kept in a group of at least 6 individuals to show schooling behaviors and prevent intimidation of weaker fish.

Coloration and Sexual Dimorphism: Breeding males turn a deep, dark ruby-red on the front half of the body with dark vertical bars. Females are yellowish with less distinct black bars.

Care, breeding and tankmates

Aquarium Setup: An 80-liter tank is recommended. Plant densely along the sides and back, leaving the center open for swimming. Add driftwood and smooth pebbles to replicate the stream bed.

Diet and Feeding: Omnivorous. Readily accepts flakes, granules, and frozen foods like brine shrimp and daphnia. Incorporate vegetable flakes to provide a balanced diet.

Water Quality: Prefers soft, slightly acidic water. Keep temperature at 20-26°C, pH 6.0-7.0, and GH 5-12 dGH. Regular partial water changes are essential.

Compatibility and Cohabitation: Great community fish. Suitable tankmates include tetras, rasboras, Corydoras, and other peaceful barbs. Less likely to nip fins than Tiger Barbs.

Aquarium Breeding: Spawns among fine plants. Spawning usually occurs in the morning. Remove parents immediately after to prevent egg eating.

Risks and Diseases: Susceptible to ich if exposed to sudden water temperature changes. A secure cover is needed as they are active and can jump.

Fish profile

Temperament
Pacifico
Diet
Onnivoro
Tank level
Metà
Minimum group
6
Adult size
6 cm
Minimum tank volume
80 L
GH
5 dGH - 12 dGH
KH
2 dKH - 6 dKH
TDS
n/a
Conductivity
n/a
Feeding frequency
1-2 volte al giorno
Bioload
Medio
Flow
Moderato
Jump risk
Covered tank required
Reproduction
Facile da riprodurre in acqua tenera e acida. Depone uova adesive tra la vegetazione fitta.
Compatibility & tankmates
Meno aggressivo rispetto ad altri barbi, non morde le pinne dei coinquilini se tenuto in gruppo.

Ecological Estimates & Biological Models

Trophic level
2 ± 0 se
Resilience
High (less than 15 months)
Phylogenetic uniqueness (PD50)
0.5
Bayesian Length-Weight
a = 0.01047, b = 3
VulnerabilityLow vulnerability (10 / 100)

Image gallery

Licensed images linked to the species or, when marked, to the closest representative taxon.

Related species

Other recommended species with similar care requirements and water parameters.

Last updated: 06/13/2026