Barilius ardens (3–4 cm) – a vibrant, fast-swimming freshwater fish with metallic blue and orange hues. Perfect for well-oxygenated, active community tanks.

The Barilius ardens is a stunning freshwater fish species from South and Southeast Asia, admired for its vivid metallic blue body with orange-red fin highlights. Known for its active, schooling behavior and shimmering colors, this fish is ideal for river-style aquariums with strong currents and a well-oxygenated environment.

At 3–4 cm, these juveniles are small but already display their iridescent charm. Adult Barilius species generally grow to 8–12 cm, making them suitable for medium to large aquariums. Due to their energetic swimming style, they are best kept in groups to mimic their natural schooling habits in fast-flowing streams.

✅ Key Features

• Size: 3–4 cm juvenile; adults reach 8–12 cm

• Temperament: Active and peaceful when kept in groups

• Care Level: Moderate (requires current and oxygen-rich water)

• Lifespan: 4–6 years in proper conditions

• Special Trait: Brilliant metallic body with vivid orange accents on fins

Care Guide for Barilius ardens

✅ Tank Requirements

• Minimum Tank Size: 100 liters (30 gallons) for a small school

• Aquascape: Sandy or gravel substrate with rocks and driftwood to replicate river habitat

• Filtration: High-flow filtration system to maintain strong currents

• Lighting: Moderate to bright to highlight iridescent scales

• Additional Equipment: Powerhead or wavemaker for water movement

✅ Water Parameters

• Temperature: 20°C – 26°C (68°F – 79°F)

• pH Level: 6.5 – 7.8

• Water Hardness: 5–15 dGH

• Maintenance: Weekly 30–40% water changes to keep water fresh and oxygen-rich

✅ Feeding Habits

Barilius ardens are omnivorous with a preference for protein-based diets.

• Recommended Diet:

  • High-quality micro pellets or flakes

  • Frozen or live foods (brine shrimp, bloodworms, daphnia)

  • Occasional vegetable matter (blanched spinach or spirulina flakes)

Feed 2–3 small meals daily to support their high energy needs.

✅ Tank Mates

This species is peaceful when kept in groups of 6 or more, reducing stress and aggression.

Suitable Companions:

• Other fast-swimming riverine fish (Danios, Rasboras)

• Bottom dwellers like Loaches and small Catfish

• Avoid slow-moving or long-finned species (they may nip fins)

✅ Behavior & Personality

• Behavior: Highly active and loves swimming in strong currents

• Activity: Mid-water schooling fish; thrives in groups

• Special Note: Can become aggressive in small numbers, so always keep a school

Why Choose Barilius ardens?

• Brilliant metallic blue and orange coloration for a dazzling display

• Perfect for biotope aquariums replicating fast-flowing streams

• Active, schooling behavior for dynamic aquascapes

✅ Ideal for river-style setups with strong currents
✅ A rare and beautiful species for experienced aquarists