Cardinal Tetra Care Guide
Paracheirodon axelrodi · Moderate care · 20 gallon minimum
Like a neon but bigger and fully red-striped; dazzling in large schools in soft, planted blackwater.
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How big does a cardinal tetra get?
A cardinal tetra (Paracheirodon axelrodi) reaches about 2.0 inches as an adult. Plan tank size and tank mates around the adult size, not the small fish you buy at the store.
Tank size & setup
Give a cardinal tetra a minimum of 20 gallons, with water at 73–81°F and a pH of 5.5–7. Keep them in groups of at least 6 — they are shoaling fish and become stressed and washed-out alone. As a moderate-care, omnivore species, a stable, cycled tank with the right diet keeps them healthiest.
Good tank mates
Pair a cardinal tetra with peaceful species that share its temperature and pH range. Compatible options include:
- Neon Tetra — 1.5", 10g min
- Guppy — 2.0", 10g min
- Molly — 4.0", 20g min
- Platy — 2.5", 10g min
- Zebra Danio — 2.0", 10g min
About the cardinal tetra
The cardinal tetra is a species of freshwater fish of the family Acestrorhamphidae, the American characins, of order Characiformes. It is native to the upper Orinoco and Negro Rivers in South America. Growing to about 3 cm (1.2 in) in total length, the cardinal tetra has the striking iridescent blue line characteristic of the genus Paracheirodon laterally bisecting the fish, with the body below this line being vivid red in color, hence the name "cardinal tetra". The cardinal tetra's appearance is similar to that of the closely related neon tetra, with which it is often confused; the neon's red coloration extends only about halfway to the nose, and the neon's blue stripe is a less vibrant blue.
Recommended gear for cardinal tetras
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