Cardinal Tetra – Paracheirodon axelrodi – 2 to 2.5 cm

Cardinal Tetra – Paracheirodon axelrodi

The Cardinal Tetra (Paracheirodon axelrodi) is one of the most iconic small Amazonian fish in the aquarium hobby. Its body features a remarkable electric-blue stripe accompanied by intense red colouration extending along much of the lower part of the body.

The specimens offered here are approximately 2 to 2.5 cm.

Adult Size

The Cardinal Tetra generally reaches around 4 to 5 cm as an adult.

Water Parameters

This species appreciates soft to moderately mineralised water that is slightly acidic to neutral.

Temperature: 24 to 28 °C
pH: 6 to 7.5
KH: 2 to 10 °dKH
Nitrite: 0 mg/L

Nitrite should remain undetectable. Clean, stable and properly filtered water helps keep the shoal in good condition.

What Size Aquarium for Cardinal Tetras?

An aquarium at least 60 cm long can provide a suitable basis for a small group, although a larger aquarium allows a bigger shoal to be kept and gives the fish more room to display their natural behaviour.

A planted aquarium with plenty of vegetation combined with open swimming areas is particularly suitable for this species.

Behaviour and Shoaling

The Cardinal Tetra is a peaceful and strongly sociable fish and should not be kept alone.

A group of at least 10 individuals is recommended. When aquarium size allows, a larger shoal is even better and encourages the fish to display more of their natural behaviour.

Feeding

In the wild, the Cardinal Tetra feeds mainly on small invertebrates, larvae and other micro-organisms.

In the aquarium, it readily accepts foods suitable for its small mouth, including micro-pellets, finely crushed flakes and small frozen or live foods such as Artemia and Daphnia.

Breeding

The Cardinal Tetra is an egg-laying fish. The eggs are scattered amongst vegetation or over the substrate.

Breeding in the aquarium is possible but can be challenging. Very soft water and suitable conditions for the development of the eggs and fry are particularly important.

Origin

Paracheirodon axelrodi originates from South America, particularly the Rio Negro and Orinoco basins.

In the wild, the species inhabits waters that are often soft and acidic, in environments rich in vegetation and organic matter.

Lifespan

The Cardinal Tetra can live for approximately 4 to 6 years in an aquarium when kept under suitable conditions.

Never Release Aquarium Fish into the Wild

Cardinal Tetras must never be released into a river, pond, lake or any other natural environment.