
Cardinal Tetra
Paracheirodon axelrodi
Description
The Cardinal Tetra is considered the ideal tank mate for discus. Native to the Rio Negro, it naturally lives alongside wild discus. With its bright blue-and-red stripe, it moves in spectacular schools.
🌍 Origin
Rio Negro, Brazil — the same Amazon basin as wild discus.
Appearance
A neon-blue horizontal stripe followed by vivid red on the lower half. 4–5 cm at maturity.
Recommended water parameters
Compatibility with discus
The best tank mate for discus — NOT the common neon (P. innesi), which prefers 22–26°C. The Cardinal is built for warm water.
Care
Keep in large groups for natural behavior. Prefers soft, slightly acidic water. Diffused lighting.
Feeding
Omnivore — micro-pellets, brine shrimp, daphnia, bloodworms. Feed 1–2x/day in small portions.
Behavior
Peaceful and gregarious, lives in tight schools. Does not nip discus fins.
💡 Practical tips
- →Choose the CARDINAL, not the common neon — the temperature difference is critical
- →At least 10–15 specimens for a natural school
- →Introduce them before the discus to let them settle in
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