Slippery dick wrasse

This species is native to the tropical and subtropical waters of the Western Atlantic Ocean. Its wide range extends from the coast of North Carolina (USA) and Bermuda down to southern Brazil, including the Gulf of Mexico and the entire Caribbean Sea. It inhabits shallow coral reefs, seagrass beds, and sandy flats mixed with coral rubble at depths ranging from 1 to 15 meters. It is frequently observed around harbors and docks.

Belonging to the family Labridae, Halichoeres bivittatus features an elongated, cylindrical body with a pointed snout and a small terminal mouth containing projecting canine-like teeth. Its skin is covered with a thick, slippery layer of protective mucus (hence the common name). Adults can reach a maximum total length of approximately 20-25 centimeters, though they stay smaller in tanks.

It is an extremely active, curious, and bold diurnal swimmer. It spends the day actively searching the substrate and flipping small rocks to find food. At dusk or when threatened, it dives headfirst into the sand bed to sleep fully buried for the night. It displays strong territorial behavior toward conspecifics.

The coloration changes dramatically as the fish matures. Juveniles and females (initial phase) have a pale or white body with two prominent dark longitudinal stripes running along the sides. Terminal phase males are highly colorful, displaying green, pink, and yellow hues with a black spot on the dorsal fin and tail base. It is a protogynous hermaphrodite.

Requires a marine aquarium of at least 350-400 liters. The most critical requirement is a deep bottom layer of fine, soft sand (at least 8-10 cm, non-silica sand) to allow for its natural burying behavior. The live rock decoration must be placed directly on the bottom glass to prevent collapses caused by its continuous digging.

A voracious carnivore. In nature, it feeds on crabs, hermit crabs, mollusks, sea urchins, and polychaete worms. In captivity, it readily accepts almost any frozen food, such as mysis shrimp, brine shrimp, krill, and chopped clam meat. It will also consume dry pellets with enthusiasm. It is excellent for controlling flatworms and snails.

Requires stable marine parameters: temperature between 22°C and 26°C, pH between 8.1 and 8.4, specific gravity (SG) of 1.020 to 1.025, and carbonate hardness (KH) of 8 to 12 dKH. A powerful protein skimmer and efficient filtration are necessary to handle the organic waste from its heavy feeding. Regular water changes are required.

Not safe for small invertebrates; it will readily prey on ornamental shrimp, small crabs, snails, and sea urchins. However, it is completely reef safe regarding corals. It houses well with active, robust tankmates like tangs, large angelfish, damsels, and other larger wrasses. Do not house more than one specimen per tank.

Captive breeding in home aquariums has not been achieved. They are sequential protogynous hermaphrodites and broadcast spawners. Gametes are released into the open water column where eggs drift. Rearing the resulting planktonic larvae is extremely difficult in closed systems due to their micro-food requirements.

The primary risk is skin damage or physical trauma if a proper sand bed is not provided. Attempting to burrow into coarse gravel can cause severe abrasions, leading to secondary infections. It is a strong jumper, so a tight lid or mesh screen is mandatory to prevent it from jumping out of the tank.