Zoramia leptacanthus is a diminutive, laterally compressed cardinalfish that matures at roughly 2.5 inches. The body is semi-transparent to yellowish-silver, marked with iridescent blue around the eyes and blue and yellow accents across the forward half of the body, and the first of its two dorsal fins is drawn out into the elongated filament that gives the species its common name. It occurs widely through the Indo-Pacific, from the Red Sea and Mozambique east to Samoa and Tonga, north to the Ryukyu Islands and south to New Caledonia, with aquarium specimens typically collected out of Indonesia. In the wild it gathers in dense, often mixed-species aggregations across sheltered lagoons and bays in shallow water of about one to twelve meters, usually hovering among the branches of stony corals. Unlike most cardinalfish, which shelter alone through daylight hours, this species is diurnal and schools openly in the water column.

Adults should be housed in an aquarium of at least 30 gallons, sized for a group rather than a single specimen, because a school of five or more is what gives these fish the confidence to hold station in open water instead of retreating into the rockwork. Structure matters as much as volume: thickets of branching coral such as Acropora, or even long urchin spines, provide the vertical framework the school naturally orients to, and a generous ledge or cave gives them a retreat under intense reef lighting. Gentle water movement suits them, and subdued or transitional dusk and dawn lighting brings out their best display, though captive specimens usually settle into daytime activity. A mature system with well-developed rockwork and established coral structure reflects the habitat they come from and is the surest path to a settled group.

Care sits at a moderate level, driven less by water chemistry than by the need to buy the fish in sufficient numbers, pair them with quiet tankmates, and make certain every individual in the school is actually getting food.