Tetra Cardinal (Paracheirodon axelrodi)

The Cardinal Tetra is a vibrant and peaceful freshwater fish known for its striking red and blue coloration. Unlike the similar Neon Tetra, which has a shorter red stripe, the Cardinal Tetra’s red runs the full length of its body, making it a standout in any aquarium. Native to the Amazon River Basin, this species thrives in well-maintained, planted tanks and is perfect for community setups.

Care Guide

• Scientific Name: Paracheirodon axelrodi
• Common Name: Cardinal Tetra
• Family: Characidae
• Origin: South America (Brazil, Venezuela, Colombia – Amazon & Orinoco River Basins)
• Adult Size:Up to 2 inches (5 cm)
• Lifespan:3–5 years
• Temperament:Peaceful, schooling fish
• Diet:Omnivore – enjoys high-quality flakes, micro pellets, frozen, and live foods (brine shrimp, daphnia, bloodworms)
• Tank Size:Minimum 10 gallons (best in 20+ gallons for a larger school)
• Water Parameters:
  • Temperature: 73–82°F (23–28°C)
  • pH: 4.0–7.0 (prefers soft, slightly acidic water)
  • Hardness: 1–8 dGH

Tank Setup

• Best kept in groups of 6 or more to encourage natural schooling behavior.
• Prefers a planted tank with driftwood, leaf litter, and a dark substrate to mimic their natural blackwater environment.
• Dim lighting enhances their colors and reduces stress.
• Ideal tankmates include Corydoras, Rasboras, peaceful Gouramis, Otocinclus, and other small Tetras.

Interesting Facts

• Often confused with Neon Tetras, but Cardinals have a full-body red stripe, while Neons have only a partial red stripe.
• Sensitive to water quality changes, so stable conditions are essential.
• Wild-caught Cardinals can be delicate, but tank-bred specimens are generally hardier and adapt better to aquarium life.