Can Bolivian Ram Live With Cardinal tetra?

The Bolivian ram's own profile recommends exactly this kind of tankmate: a peaceful, open water characid whose presence helps reduce the ram's natural shyness by signalling there is no danger nearby. The size gap looks larger on paper than it plays out in the tank, since the ram feeds by sifting the substrate for invertebrates rather than hunting fish.

24 to 28 °C and pH 6 to 7.5 suit both without adjustment.

Buy the cardinal tetra as a full shoal, 8 to 10 or more, and keep the rams as a mixed sex group of six to eight if the tank is large enough, 120 cm or more in length, since this species is more gregarious than its German cousin. Soft sand lets the rams sift naturally, and a 180 litre tank, the Bolivian ram's own minimum, comfortably holds both a ram group and a cardinal shoal.