Cardinal Tetra

Cardinal Tetra, Paracheirodon axelrodi, have been a staple in the freshwater fish hobby for decades. They are endemic to the upper Orinoco and Negros Rivers in South America. Growing to just over an inch (1.2), these fish sport the classic iridescent blue line of the Paracheirodon family along the top half of their body and a vivid red colouration along the lower half. 

They're a great community fish and prefer to be kept in schools of 6 or more, like other tetra species. They prefer tropical temperatures between 73–81°F (23–27°C) and a lower pH range from 4-6 but can tolerate a wider range of pH.