AquaGuide

Cardinal Tetra Care Guide

Paracheirodon axelrodi

Key Takeaways

  • Cardinal Tetra needs at least 15 gallons, with 20 gallons preferred.
  • Keep water between 24-28°C and pH 4.5-6.5.
  • Keep a group of at least 6 to reduce stress.

Quick Facts

Difficulty: intermediate
Min Tank: 15 gallons
Size: 5 cm
Group: 6+
Temperature: 24-28°C
pH: 4.5-6.5
Temperament: peaceful
Swimming: middle
Diet: omnivore
Lifespan: 4-6 years

Care Overview

Cardinal tetras are similar to neon tetras but with more vibrant, full-body red coloring. They require softer, more acidic water than neon tetras.

Ideal Tank Setup

A 15+ gallon planted tank with soft, acidic water. They need stable water parameters and are more sensitive than neon tetras. Include floating plants and driftwood.

Diet and Feeding

Small flake food or micro pellets. Supplement with frozen or live daphnia and brine shrimp. Feed small amounts 2-3 times daily.

Best Tank Mates

  • Other tetras
  • Rasboras
  • Corydoras
  • Shrimp

Fish to Avoid

  • Large fish
  • Fish needing hard, alkaline water

Common Problems

  • Sensitivity to water parameters
  • Fading color from stress

Common Beginner Mistakes

  • Using a tank smaller than 15 gallons, which makes water quality harder to keep stable.
  • Ignoring adult size, group size, or temperament when choosing tank mates.
  • Changing too much water or filter media at once before checking ammonia and nitrite.

Frequently Asked Questions

What is the difference between cardinal and neon tetras?

Cardinal tetras have red along their entire lower body, while neon tetras only have red on the back half. Cardinals need softer, more acidic water.

Related Tools

Sources and Review Process

  • Freshwater aquarium husbandry references for water quality, tank size, and stocking guidance.
  • Species profiles and compatibility rules maintained in the TankWise data set.
  • Aquarium health guidance is educational and should not replace an aquatic veterinarian for severe symptoms.

More Cardinal Tetra Guides