Katherine's Fairy Wrasse saltwater fish care guide

Cirrhilabrus katherinae is a compact fairy wrasse from the western Pacific, recorded from the Izu Islands of Japan, the Mariana region, and the Caroline Islands. Females and juveniles are nearly uniform orange-red, while mature males take on far more structure and contrast: red along the dorsal surface, a sharply defined white underside, dark banding in the fins, elongated pelvic fins, and brilliant blue bands tracing the dorsal and anal fins. In the wild this species favors exposed outer reef slopes rather than lagoons or harbors, typically between roughly 10 and 40 meters, with occurrences reported as deep as 50 meters.

Adult housing should be an established marine system of at least 90 gallons, built around generous live rock with clear lanes of open water for cruising. Caves and narrow crevices matter as much as the open space, since fairy wrasses do not bury in sand; instead they wedge themselves into rockwork at night and may form a mucus cocoon. A tightly fitted cover or screen top is not optional, as this species is a documented jumper from open aquariums. Subdued lighting during the first days after introduction helps, because specimens can be sensitive following transport and initial acclimation.

On exposed outer reefs, Katherine's Fairy Wrasse feeds on zooplankton picked from the water column, and that planktivorous habit shapes how it should be fed in captivity. This is a carnivore that responds best to small, meaty marine items rather than large single portions.

Offer enriched frozen mysis and brine shrimp, finely chopped squid, fish flesh, shrimp and clam, other small meaty marine preparations, and appropriate marine flakes or pellets. Two or three feedings per day suit an established fish, and newly introduced specimens benefit from more frequent small offerings while they settle. Pairing that feeding schedule with dimmed lighting during the first several days encourages a hesitant new arrival to begin eating.

Enriched Frozen Mysis Shrimp Enriched Brine Shrimp Chopped Squid Chopped Fish Flesh Chopped Clam Small Meaty Marine Foods Marine Flakes Marine Pellets
Wild individuals occur in aggregations over outer reef terrain, and in the aquarium this is an active, conspicuous swimmer that spends most of the day working the water column above and around the rock. A newly added specimen may stay hidden for several days before establishing a routine. Temperament reports are not unanimous: the species is generally described as mild-mannered for a wrasse, but some accounts note that it can display aggression, so treat it as semi-aggressive when planning a stocking list.

Choose tankmates that will neither intimidate it nor outcompete it at feeding time, and give the fish enough open swimming room to avoid friction with established territory holders. Species-specific guidance on keeping pairs, harems, or more than one male together is not well documented, so caution is warranted with conspecifics. Reef compatibility is strong, with no recorded harm to corals or other invertebrates, and no documented predation on shrimp, crabs, snails, clams, or small fish.

FAQ

Frequently Asked Questions

About the Katherine's Fairy Wrasse

  • How large an aquarium does an adult Katherine's Fairy Wrasse need?
    Plan on a minimum of 75 gallons for an adult. The system should be established and furnished with live rock, sheltering crevices, and ample open swimming space.
  • Is this wrasse safe in a reef aquarium?
    Yes. It is considered reef safe with corals, fish, and invertebrates, with no documented predation on shrimp, crabs, snails, or clams.
  • How should a newly acquired specimen be settled in?
    Feed small meaty foods such as enriched mysis and brine shrimp, chopped marine flesh, and suitable marine pellets or flakes several times daily at first. Keep lighting subdued for the first few days, since the species can be sensitive after transport.