Black Ruby Barb

fish description – Black Ruby Barb Care Guide ($Pethia\ nigrofasciata$)

Category	Detail
Scientific Name	$Pethia\ nigrofasciata$ (formerly $Puntius\ nigrofasciatus$)
Common Name	Black Ruby Barb, Purplehead Barb
Origin	Forest streams and river basins of Sri Lanka
Adult Size	2–2.5 inches (5–6.5 cm)
Temperament	Peaceful, active, mid-level schooling fish, can be slightly nippy
Lifespan	3–5 years
Care Level	Easy

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Appearance and Sexual Differences

 

• Short Description: This fish is characterized by a high, compressed body and several dark vertical bars (which may fade with age). Mature males gain an intense, deep ruby-red hue across the body and head, making them a visually stunning addition to the aquarium.
• Coloration: Juveniles are pale, yellowish-grey with bold black bars. Males develop a spectacular ruby-red coloration across the entire body, with the dark bars often turning a velvety black. The dorsal fin of a breeding male is usually solid black. Females are paler, slightly larger, and retain a more bronze or yellow-grey color.
• Fins: The male’s pelvic and anal fins may also be reddish-black.
• Behavior: They are active but somewhat shy fish that thrive when kept in a large school. They are less boisterous than Tiger Barbs but will show occasional playful chasing and may nip long-finned, slow-moving fish if not kept in a large enough group.

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Tank Requirements and Water Parameters

 

• Minimum Tank Size: 20 gallons (75 liters) is the minimum for a school of 6–8 fish. A 30-gallon tank or larger is better to accommodate their activity and reduce stress/aggression.
• Schooling: Must be kept in schools of at least 6 individuals or more (10+ is ideal). A larger school is crucial for keeping their attention focused internally, which reduces stress and potential fin-nipping toward other species.
• Temperature: Cooler Tropical range: $68^\circ$–$78^\circ\text{F}\ (20^\circ$–$26^\circ\text{C})$. They prefer temperatures on the lower end of the tropical range.
• pH Level: Soft, slightly acidic water is highly preferred: 6.0 to 7.5 (ideal range $6.0$–$6.5$). They are sensitive to poor water quality and sudden changes in chemistry.
• Aquascape: They prefer a heavily planted tank with plenty of cover, driftwood, and rocks to create shaded areas. A dark substrate and subdued lighting (via floating plants) will maximize the male’s ruby coloration. Ensure open space is available for swimming.

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Diet and Feeding

 

The Black Ruby Barb is an omnivore that benefits from a diet rich in vegetable matter.

• Staple Diet: High-quality flake food or micro-pellets. They are often bottom-feeders in the wild, grazing on detritus and algae.
• Supplementation: A varied diet including both protein and greenery is important. Offer frozen or live foods regularly: Bloodworms, Brine Shrimp, and Daphnia. Supplement frequently with spirulina or blanched vegetables (e.g., spinach) to satisfy their vegetable requirements.
• Schedule: Feed small amounts 2–3 times per day. They are enthusiastic eaters, so ensure food is consumed quickly.

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Compatibility

 

• Caution: Should not be housed with slow-moving, long-finned fish (e.g., Angelfish, Bettas, Fancy Guppies) due to potential fin-nipping behavior.
• Good Tank Mates: Other small, active, and robust fish that occupy different water columns. Examples include Corydoras catfish, Danios (Zebra, Giant), peaceful Tetras (Black Skirt, Serpae), Rasboras, and Loaches.