Can Siamese fighting fish Live With Cardinal tetra?

Cardinal tetras like warm water, which suits a betta better than neons do. The cardinal's range runs 23 to 29 °C against the betta's 22 to 30 °C, and both manage pH 6 to 7.5, so on water alone this is an easy pairing.

The limits are social. Cardinals should be bought as a mixed-sex group of at least 8 to 10, ideally with other schooling fish for security, which means a tank with a base of at least 60 by 30 cm. The ornamental betta, for its part, is unsuitable for the standard community tank and best kept alone, with tolerant individuals the exception.

If you try it, add the cardinals as a full school rather than a handful, keep the tank heavily planted with subdued light, as the cardinals prefer, and be ready to separate them if the betta starts chasing. Feeding is simple, because both eat small foods: fine flake, micro pellets and small live or frozen foods for the cardinals, and bloodworm, Daphnia and quality pellets for the betta.