“Beauty is only skin deep.” This is certainly the case with the florid sixline wrasse (Pseudocheilinus hexataenia). While it may look like an adorable little fish, the sixline wrasse can terrorize fish communities in certain aquarium setups. That said, in the right aquariums, they can also be joyful little fish to keep.
Difficulty: Once acclimated, the sixline wrasse is a fairly sturdy aquarium inhabitant. Acclimation can be impacted if the sixline wrasse is harassed by its tankmates or if shelter sites are in short supply. The sixline wrasse is not a finicky fish and will eat meaty foods, which should be offered to it once a day (more often if the aquarium is new or free of a good community of microfauna for it to forage on). The sixline wrasse will consume frozen fare (e.g., mysids, fish eggs, prepared foods), and some individuals will even eat flake food. Fortunately, the sixline wrasse rarely exhibits fading of its bright colors.
Physical description: The sixline wrasse is purplish blue overall with orange lines down the body and a bright green tail. There is a black eye spot just before the tail. The sixline wrasse reaches a whopping 3 inches in total length.
The most similar species in the genus is the fourline wrasse (P. tetrataenia). This wrasse is purple above, dark green below, with blue lines down the flanks and back. The fourline wrasse is known from Palau to the Hawaiian Islands and is similar in husbandry and disposition to P. hexataenia.
Range: The sixline wrasse occurs from the Red Sea and East Africa to the Tuamotus and Johnston islands. The sixline wrasse lives on lagoon patch reefs, coral pinnacles and reef faces with rich stony coral growth. The sixline wrasse tends to shelter among the branches of ramose coral species. Pseudocheilinus hexataenia is known from a depth range of less than 3 to at least 115 feet. The sixline wrasse is haremic, with a male defending a small group of females. The sixline wrasse feeds on a variety of tiny crustaceans, shelled–protozoa (foraminiferans) and minute snails.
Compatibility: The sixline wrasse has led many an aquarist to the edge of insanity! How could such a cute little fish be so mean? Once the sixline wrasse has become established, especially in more diminutive aquariums, it will often do its best to destroy any new fish of equal or lesser size added after it. That said, the sixline wrasse could be kept with more docile species as long as the latter are well-adapted to the aquarium home before P. hexataenia becomes a community member. When the shoe is on the “other fin,” this bad boy is the first to succumb to a beating. If added to an aquarium of hellions, the sixline wrasse is likely to hide out and starve to death. The sixline wrasse tends to be best behaved if added to a large aquarium that is full of hiding places and with larger species (e.g., butterflyfish, angelfish, surgeonfish and rabbitfish).
It is not unusual to see a sixline wrasse inspecting and cleaning larger fish. I would only keep one sixline wrasse per aquarium unless you can acquire a male and a female or two females. The sixline wrasse is a protogynous hermaphrodite, which means if you place two females in an aquarium, one may change to a male. Likewise, if you add two juvenile sixline wrasses — you are likely to end up with a pair.
If you have two P. hexataenia that start fighting, one of the fish will have to be removed. The sixline wrasse will do well in the invertebrate aquarium. The only inverts the sixline wrasse may damage are small ornamental shrimp (e.g., anemone shrimp) and smaller crabs (e.g., porcelain crabs).
The sixline wrasse is a known predator of the small snails (members of the family Pyramidelidae) that are parasites of tridacnid clams. While the sixline wrasse may eat them if exposed during the day, these snails usually hide when the lights are on and come out at night when any P. hexataenia would be sleeping.
Aquarium conditions: While it can be kept in an aquarium as small as 10 gallons, the sixline wrasse shouldn’t be kept with other fish in an aquarium this small. If you want to keep the sixline wrasse with more docile fish, the larger the aquarium, the better! It is not a burying species of wrasse, thus a sandbed is not essential. Acceptable water parameters for the sixline wrasse are a pH of 8.1 to 8.4, specific gravity of 1.019 to 1.025 and a water temperature of 76 to 82 degrees Fahrenheit.
Breeding: Reports of the sixline wrasse spawning in captivity are rare.