Iridescent Cardinalfish

About

The iridescent cardinalfish (Pristiapogon kallopterus) is one of those reef fish that rewards a closer look. Its scales carry a soft, shifting sheen that becomes more apparent under good aquarium lighting, even if it won't outshine the corals around it. This species has an enormous natural range, turning up from the Red Sea all the way east to the Pitcairn Islands and north to Hawaii and southern Japan, which speaks to how adaptable it is as a species. In the wild it occupies clear-water lagoon patch reefs and deeper seaward slopes, typically down to around 45 meters, hovering in that benthopelagic zone just above the substrate. It is naturally a solitary animal and a nocturnal hunter, picking off small crustaceans in the dark. In an aquarium setting those instincts translate reasonably well. It is peaceful toward tankmates and unlikely to cause trouble in a community reef. It does appreciate some cover, a cave or overhang where it can retreat during bright periods of the day. As a carnivore it needs meaty foods like mysis, small frozen crustaceans, or similar fare. Given its forgiving temperament and robust constitution, it is a solid choice even for hobbyists still building their saltwater experience.