Cardinal Tetra (Paracheirodon axelrodi) – 2–2.5 inches

🐠 Species Overview

The Cardinal Tetra (Paracheirodon axelrodi) is a small, peaceful, and vibrant freshwater fish native to the blackwater and clearwater streams of the Amazon Basin in South America. It is prized for its iridescent blue body and bright red stripe that extends from the middle of the body to the tail. Cardinals are schooling fish and show their best colors and behavior when kept in groups of 6 or more.

🏡 Aquarium Setup & Care Instructions

Tank Size & Environment

• Minimum Tank Size: 20 gallons (75 liters) for a small school.

• Substrate: Fine gravel or sand with a dark substrate to enhance colors.

• Decor: Dense plantings, driftwood, and floating plants provide hiding spots and soft lighting.

• Water Parameters: Temperature 73–81°F (23–27°C), pH 5.5–7.0, soft to moderately hard water.

• Filtration: Gentle filtration with minimal current; sensitive to ammonia and nitrites.

Behavior & Tankmates

• Peaceful and social; keep in groups of at least 6.

• Compatible with other small, non-aggressive fish like Neon Tetras, Rummy Nose Tetras, Corydoras, and small rasboras.

Diet

• Omnivorous; feed a variety of high-quality flakes, micro-pellets, and live or frozen foods such as brine shrimp, daphnia, and bloodworms.