Cardinal Tetra

Paracheirodon axelrodi

Cardinal Tetra (Paracheirodon axelrodi) — Easy care, Peaceful, under Tetra & Characin. Minimum tank in the app: 15.9 US gal min; aim for 73–84°F and pH 5.5–7.5. Cardinal Tetras are ideal for both novice and experienced aquarists seeking a vibrant shoaling species.

Care levelEasy

TemperamentPeaceful

Min tank size15.9 US gal min

pH range5.5–7.5

Temperature73–84°F

Max size1.8 in (4.5 cm)

Captive lifespan4–7 years

SchoolingYes · 6+ recommended

Captive lifespan reflects typical experience in a home aquarium, not maximum recorded age; genetics, sourcing, and care vary.

Natural distribution

Mostly South America

South America

Regional colours match the stocking calculator’s origin map.

Cardinal Tetra Tank Setup

To optimize their wellbeing, create a balanced environment with ample swimming space and plenty of cover. Use soft, dark substrates and incorporate plants to simulate their natural habitat, while maintaining a gentle water flow. Lighting should be moderate, with shaded areas to encourage natural behaviors and comfort.

What Do Cardinal Tetras Eat?

As omnivores, Cardinal Tetras thrive on micro foods and flakes, but their small mouths mean they may struggle with larger particles. Monitor feeding to ensure all individuals get their share, as competition can arise if food is not appropriately portioned.

Cardinal Tetra Tank Mates

These tetras pair excellently with similarly sized, peaceful species that occupy different swimming levels, such as small rasboras or dwarf cichlids. Avoid aggressive tank mates or large predators that might intimidate or predate on them. Intraspecies competition is minimal when kept in groups of six or more, enhancing their shoaling instincts.

Are Cardinal Tetras Good for Beginners?

In App-aquatic we file this under easy care. That still means a cycled tank, realistic stocking, and parameters that do not swing every weekend. A frequent oversight is housing Cardinal Tetras in inadequate numbers, leading to stress and diminished liveliness. ignoring water parameters can result in health issues, as these fish are sensitive to pH and temperature fluctuations.