Plain Cardinalfish

About

The plain cardinalfish (Apogon atricaudus) is a small but interesting species from the eastern Pacific, ranging from the rocky reefs around San Clemente Island in southern California down through Baja and into the Gulf of California and surrounding offshore islands. As the common name suggests, this isn't a fish that dazzles with color. It's a fairly understated little cardinalfish, and its appeal lies more in its behavior and the niche it fills than in its appearance. Like most cardinalfishes, it's a creature of habit that tucks itself into rockwork and crevices during daylight hours, only venturing out more actively once the lights go down. In the wild it picks off crustaceans, mollusks, and other small invertebrates, so in an aquarium setting you'll want to make sure it's getting meaty foods. A well-structured tank with plenty of hiding spots will help it settle in and feel secure. It's listed as intermediate in terms of care, so some prior experience with marine fish will serve you well here. Reaching just under three inches at most, it fits comfortably into a reasonably sized reef or fish-only setup, as long as tankmates aren't large enough to view it as a snack.