Cardinal Tetra Care Guide
Paracheirodon axelrodi · Freshwater Fish
What Cardinal Tetra look like
The Cardinal Tetra (Paracheirodon axelrodi) exhibits a strikingly vibrant coloration, characterized by a laterally compressed, fusiform body that typically reaches a maximum adult size of approximately 1.5 to 2 inches (4-5 cm). This species displays sexual dimorphism, with females generally being slightly larger and more rounded than males, particularly when gravid. A distinctive feature of the Cardinal Tetra is the vivid electric blue horizontal stripe that runs along the upper body from the snout to the caudal fin, contrasting sharply with the entire lower body, which is adorned with a deep, vivid red hue extending from the jaw to the caudal fin. This red coloration is more pronounced than in the closely related Neon Tetra (Paracheirodon innesi). The species possesses a well-developed lateral line system, aiding in the detection of vibrations in the water, and exhibits a small adipose fin, which is characteristic of many tetras. The dentition is small and conical, adapted for a varied diet, while the overall body shape is streamlined for efficient swimming in its natural habitat.
Behavior & temperament
Cardinal Tetras are social fish that thrive in groups, exhibiting a strong tendency to form schools in the wild, which provides safety in numbers. They are primarily pelagic, dwelling in the upper to mid-water column of slow-moving streams and flooded forest areas. Their breeding behavior is characterized as egg scatterers, where females release eggs in the water column, allowing for external fertilization by males. In terms of temperament, Cardinal Tetras are generally peaceful and non-aggressive, making them suitable for community tanks. However, they can exhibit shyness if kept in insufficient numbers, thus it is recommended to maintain them in groups of six or more to promote natural behaviors and reduce stress.
Diet & feeding
In their natural habitat, Cardinal Tetras are omnivorous, feeding on small invertebrates, zooplankton, and plant matter. In captivity, they require a varied diet that includes high-quality flake food, micro-pellets, and live or frozen foods such as brine shrimp and daphnia to ensure optimal health and coloration.
Behind the name
Paracheirodon (near hand-tooth); axelrodi (named in honor of Dr. Herbert R. Axelrod, an influential aquarist and author).
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Cardinal Tetra?
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