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Maximum size : 5 cm

Cardinal Tetra - Paracheirodon axelrodi : Complete Fish Profile & Care Guide

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The captivating Cardinal Tetra (Paracheirodon axelrodi) is undoubtedly one of the most popular aquarium fish species. This delightful species is often mistaken for the Neon Tetra due to their striking similarities in appearance. As a beginner-friendly species, the Cardinal Tetra is a relatively hardy and easy-to-care-for fish that is vibrant in color. Known for their peaceful demeanor, they make a fantastic addition to any community aquarium, or you can choose to create a species-only aquarium to fully appreciate their remarkable characteristics.

These sociable fish are best kept in larger groups of at least eight, if not more, to create a dazzling and mesmerizing shoaling effect that will quickly become the focal point of your aquarium. Furthermore, Cardinal Tetras are much more confident and colorful when in the company of others of their kind. They can become stressed and shy and even lose their color when kept alone. When it comes to ideal tankmates for Cardinal Tetras, they do well with other Tetras, Hatchetfish, Pencilfish, Corydoras Catfish, and non-aggressive, small to medium-sized Cichlids. However, it is best to avoid much larger or more aggressive fish as they can quickly intimidate them.

It is worth noting that Cardinal Tetras are more susceptible to poor water quality than their Neon cousins and prefer heavily planted aquariums that replicate their natural habitat. A soft sandy substrate, driftwood roots, and branches are ideal, while adding dried leaf litter can create a more natural feel and offer additional cover for your fish. The slender and torpedo-shaped Cardinal Tetra's body exhibits a blue and red coloration, with an iridescent blue stripe that runs from the tip of the nose and stops at the tail's base. Below this, you'll notice a wider, bright red band that runs down the entire length of the body and through the transparent tail. All fins are transparent, and the belly is usually white. Gold and silver Cardinal Tetras are available, but they are far less common. Overall, the Cardinal Tetra is an excellent choice for any aquarist, whether you're a beginner or an experienced hobbyist looking to add an eye-catching and delightful species to your collection.

Cardinal Tetra Photos

Sexual Dimorphism

The Cardinal Tetra, both male and female, exhibit similar physical attributes and coloration during their early development stages, posing a challenge in distinguishing their gender. Nonetheless, with maturation, sex differentiation becomes more apparent as the female Tetras tend to display a more conspicuous and rounded physique compared to their male counterparts, who are notably slender and exhibit a distinctive hooked anal fin.

Featured Male
Featured Female
Male Female

Quick Facts

Scientific NameParacheirodon axelrodi
Year Described1956
Other NamesRed Neon, Roter Neon
OriginsColombia Venezuela Brazil
Max Size5 cm
Aquarium LevelMiddle - Top
Best kept asGroups 6+
LifespanUp to 3 Years

Water Parameters

Water TypeFreshwater
PH3.5 - 7.5
GH1 - 5
KH2 - 6
TDS20 - 215
73 - 84
23 - 29

The Cardinal Tetra has been featured on the following stamps.

Natural habitat

Cardinal Tetras are native to the upper Orinoco and Rio Negro River Basins in South America, specifically in countries like Cambodia, Columbia, Venezuela, and Brazil. Their preferred habitats consist of serene, slow-moving waters found in creeks, rivers, canals, and streams. You can usually spot them residing in areas surrounded by lush, riparian vegetation, while their homes are made up of fallen branches, tree roots, and leaf litter. When it comes to lighting, these Tetras prefer a dimly lit environment with plenty of shade.

 Orinoco - Venezuela
Venezuela Flag
 Rio Negro - Colombia
Colombia Flag

How to breed the Cardinal Tetra

In order to breed Cardinal Tetras, it is recommended to provide them with a separate breeding tank that is dimly lit and contains very soft water, as well as abundant plant and moss coverage. It is also important to condition the fish with a diet of live and frozen foods to encourage spawning behavior. Once the female's stomach becomes full of eggs, the breeding pair should be transferred to the prepared tank. The male will then swim alongside the female as they move around the vegetation, and the eggs and sperm will be released. Successful spawning typically occurs during the evening, with the female releasing several hundred eggs. After this, it is crucial to remove the parents immediately to prevent them from consuming the eggs.

The eggs will hatch approximately three days later. Initially, the fry will be too small to consume the same foods as the adults. Therefore, it is advisable to feed them with small foods such as infusoria until they are large enough to accept more substantial meals. It is important to note that the young are sensitive to light and should be gradually acclimated to normal lighting conditions. Within 8 to 12 weeks, the fry will exhibit the same distinctive coloration as the adult Cardinal Tetras.

Diet & feeding

Cardinal Tetras are a versatile species and are known to readily accept various forms of aquarium food. However, it is advisable to provide them with a well-balanced diet that consists of high-quality dried foods, including flakes, granules, and pellets, as well as frozen and live foods such as brine shrimp, daphnia, bloodworms, and Tubifex. To further promote the overall health and vibrant coloration of the Cardinal Tetras, it is recommended to incorporate green vegetables into their diet. This will help maintain their health and ensure that the fish retain their distinct and striking appearance.

Frequently asked questions

Yes, Cardinal Tetras are very similar to Neon Tetras in their care and appearance and will frequently school together in the home aquarium.

The main difference between a Cardinal Tetra and a Neon Tetra is the length of their stripe. Cardinals stripe runs through the entire length of the body whereas the Neons stripe only runs through half of the body.\r\n

9 tank mate ideas for the Cardinal Tetra

Looking for some awesome tank mate ideas for your Cardinal Tetra? Look no further! Here are 9 of the most captivating and fascinating options that will liven up your aquarium!

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