Cryptic Six Line Wrasse (Pseudocheilinops Ataenia) saltwater aquarium fish portrait

Pseudocheilinops ataenia is a diminutive western Pacific wrasse built on a pink-to-peach base color overlaid with fine horizontal lines of yellow, orange, magenta, or red. Blue markings trace the head and fins, and the eyes are conspicuously large relative to the compact body. Males carry stronger yellow striping and more defined head markings than females. Adults reach roughly 2.6 inches, and the species is reef-associated throughout its tropical range, where it stays tucked among coral heads rather than patrolling in the open. That habitually secretive nature is what most clearly separates it from the bolder, far pushier true Six Line Wrasse it superficially resembles.

Adult housing should be a 75-gallon aquarium or larger, which affords ample feeding territory and multiple retreats for a fish that forages almost continuously. Build the interior with abundant live rock, coral-like branching structure, caves, cracks, and crevices, while leaving open lanes for swimming between shelters. A mature system matters here: established rockwork generates the resident microfauna this wrasse grazes on between feedings, so avoid placing one in a freshly cycled tank. Fit the aquarium with a tight lid, since startled individuals are capable jumpers. Care level is best described as moderate, driven largely by the need for a settled reef and small, frequent meals rather than by any difficulty with water quality.

In the wild this wrasse is a carnivore that picks amphipods and other small invertebrates from coral and coralline-algae habitat, working over surfaces methodically throughout the day. In captivity, offer appropriately small carnivorous fare: copepods, mysis shrimp, enriched brine shrimp, finely chopped seafood, other frozen preparations, and small flakes or pellets once the fish is settled. Several small feedings spread across the day suit its grazing metabolism better than one large offering, and a rock structure stocked with live microfauna fills the gaps between meals.

Acclimation deserves attention. Newly shipped specimens sometimes turn lethargic or refuse food altogether, so start with an alert individual that has been observed eating and find out what it has been receiving. Begin with those familiar items, or with live foods, then transition gradually to prepared frozen and dry diets. A mature aquarium with plenty of natural prey greatly improves the odds during this early window.

Copepods Mysis Shrimp Enriched Brine Shrimp Finely Chopped Seafood Frozen Carnivore Preparations Small Marine Pellets Marine Flakes
Wild fish occur in small groups but rarely stray far from cover, and aquarium behavior follows the same pattern. Expect a shy newcomer that spends its first days threading through rockwork, then increasingly ventures into the open as it gains confidence. Movement is deliberate and inquisitive, with the fish weaving among coral branches and rock faces in search of prey. Because wrasses can transition from female to male, keep no more than one male per system.

Temperament is peaceful and passive, making this a good fit for calm community reefs. The risk runs the other way: aggressive or bullying tankmates will intimidate it, and related Pseudocheilinus wrasses are known to chase it, so choose companions carefully and supply enough cover for quick retreats. It is reef safe and unlikely to bother hard or soft corals, clams, feather dusters, or shrimp. Keep in mind that reef safe does not extend to every small organism; amphipods, small worms, tiny snails, and various nuisance invertebrates may be hunted, while larger ornamental shrimp and established desirable invertebrates face little risk.

FAQ

Frequently Asked Questions

About the Cryptic Six Line Wrasse

  • How large an aquarium does an adult need?
    Plan on 75 gallons or more for a single adult, structured with complex live rock, branching coral forms, and numerous caves and crevices. The extra volume provides more foraging territory and more places to retreat.
  • Will it work in a peaceful community reef?
    Yes. It is peaceful and shy and mixes well with calm community fish, though aggressive tankmates and related Pseudocheilinus wrasses may chase or intimidate it. Provide many retreats and avoid housing more than one male.
  • What should I check before buying one?
    Select an alert specimen that is not lethargic and confirm that it is eating, then ask which foods it currently accepts. Introduce it to a mature aquarium rich in microfauna and offer suitably small frozen or prepared foods.