Cardinal Tetras

Cardinal Tetra – Quick Care Guide

Scientific Name: Paracheirodon axelrodi
Size: Up to 2 inches (5 cm)
Lifespan: 4–5 years (with good care)
Temperament: Peaceful, schooling fish
Tank Level: Mid-dweller

Water Parameters:

• Temperature: 73–81°F (23–27°C)

• pH: 5.0–7.0

• Hardness: Soft water preferred (1–6 dGH)

• Ammonia/Nitrite: 0 ppm

• Nitrate: <20 ppm

Tank Requirements:

• Minimum Tank Size: 15–20 gallons (for a school of 6–10+)

• Schooling: Keep in groups of at least 6, ideally 10+

• Substrate & Decor: Dark substrate, plants, driftwood, leaf litter for natural habitat feel

• Lighting: Low to moderate (enhances color and reduces stress)

Diet:

• Omnivorous:

  • High-quality flakes or micro pellets

  • Frozen/live foods: bloodworms, daphnia, baby brine shrimp

  • Feed small amounts 1–2x daily

Tankmates:

• Peaceful species only:

  • Corydoras

  • Small rasboras

  • Dwarf gouramis

  • Otocinclus

  • Shrimp (monitor for predation on baby shrimp)

Avoid: Large or aggressive fish (e.g., cichlids)

Notes:

• More sensitive than Neon Tetras—prefer mature, stable tanks

• Thrive in soft, acidic water with good filtration and regular water changes

• Stunning coloration when kept in proper conditions