Flame Cardinalfish

The Flame Cardinalfish is an understated yet elegant species native to the Western Atlantic and Caribbean, prized for its translucent ruby-red body that seems to glow under aquarium lighting. Its most distinguishing feature is a prominent dark spot located just below the second dorsal fin on the caudal peduncle, along with a dark saddle marking at the base of the tail. The body has a slightly translucent quality that allows the underlying skeletal structure to be faintly visible, giving the fish an ethereal, almost glass-like appearance that is particularly striking under blue actinic lighting.

As a nocturnal species, the Flame Cardinalfish is most active during twilight hours and after lights-out, spending the daylight hours hovering quietly among rock crevices, overhangs, and coral formations. In the aquarium, this natural behavior means the fish may appear shy or reclusive during the day, particularly when first introduced. However, most specimens gradually become bolder over time and will learn to emerge during daylight feeding times. Providing dim areas within the aquarium using overhangs, caves, and branching structures gives this species the comfort zones it needs to thrive. Groups of three to five individuals will often hover together in a loose aggregation, creating a beautiful display.

The Flame Cardinalfish is an excellent choice for beginner aquarists seeking a hardy, peaceful, and reef-safe species. It tolerates a wide range of water conditions, readily accepts prepared and frozen foods, and coexists peacefully with virtually all common reef fish. It is also one of the few marine fish comfortable in cooler subtropical water temperatures, reflecting its natural range that extends as far north as New England. Like its relative the Banggai Cardinalfish, the Flame Cardinalfish is a mouthbrooder, with males incubating eggs in their oral cavity until the fry are released as developed juveniles.