Description
Ruby Barb (Pethia nigrofasciata)
A striking, peaceful, and hardy barb known for its deep ruby-red coloration and lively schooling behavior.
📌 Basic Info
Scientific Name: Pethia nigrofasciata
Common Names: Ruby Barb, Black Ruby Barb
Family: Cyprinidae (Barbs)
Order: Cypriniformes
Origin: Sri Lanka — forest streams, shaded rivers, and shallow, slow-moving waters
Size: Up to 2.5 inches (6–7 cm)
Lifespan: 5–7 years
Tank Zone: Mid-level; active and peaceful
🌊 Water Parameters
TDS: 100–250 ppm
pH: 6.0 – 7.5
Temperature: 22 – 27°C (72 – 80°F)
Hardness: 4 – 12 dGH
🐟 Characteristics
Body: Compact, deep-bodied fish with a bronze-brown base in juveniles.
Adult Male Coloration: Turns deep ruby-red to dark red during maturity and breeding; fins become dark with black edging.
Females: Lighter, yellowish-gold body with softer markings.
Markings: Vertical black bars along the body (3 prominent stripes).
Behavior: Peaceful, social, active swimmer; displays mild chasing within the group (natural behavior).
Swimming Style: Constant, mid-level zig-zag movement.
Unique Feature: Males develop dramatic red-and-black breeding colors that make them one of the most eye-catching barbs.
Nature: Calm but lively; ideal for planted and community tanks.
🍽️ Food
Type: Omnivorous
Diet: High-quality flakes, micro-pellets, spirulina, brine shrimp, daphnia, bloodworms, blanched vegetables
Feeding: 1–2 times daily
Tip: Color-enhancing foods improve the male’s ruby-red pigmentation.
🛠️ Maintenance
Tank Size: Minimum 20–25 gallons (75–95 L) for a small school
Filtration: Moderate flow, clean and stable water
Décor: Heavily planted areas with driftwood and shaded zones (mimics natural habitat)
Substrate: Dark substrate enhances coloration
Lighting: Moderate (slightly dim preferred)
Water Change: 25–30% weekly
👥 Social Behavior
Minimum Group: 6 or more (shoaling species)
Tank Mates: Peaceful barbs, rasboras, small gouramis, danios, rainbowfish, loaches
Avoid: Fin-nippers, aggressive cichlids, large predators
✅ Do’s
Keep in groups for natural, stress-free behavior
Use plants and driftwood for shaded areas
Maintain soft, slightly acidic to neutral water
Offer varied and color-enhancing foods
❌ Don’ts
Don’t keep alone or in pairs only
Don’t house with aggressive or large fish
Don’t keep in extremely bright lighting
Don’t skip regular water changes
⭐ Quick Summary
The Ruby Barb (Pethia nigrofasciata) is a vibrant, hardy, and peaceful community fish that stands out due to the male’s stunning ruby-red coloration in adulthood. They thrive in planted aquariums, prefer to live in groups of 6+, and display lively yet calm behavior — making them an excellent choice for aquarists seeking a colorful, low-maintenance schooling fish.