Slippery Dick Wrasse

The Slippery Dick Wrasse, Halichoeres bivittatus, is a highly active Western Atlantic saltwater fish known for the dramatic changes in coloration it undergoes as it matures. Initial-phase individuals typically display a pale green, cream, or pinkish body crossed by two dark horizontal stripes, while mature terminal males become considerably more colorful, developing green to yellow-green tones, purplish lateral stripes, and intricate reddish markings across the head and tail.

Native to the Western Atlantic from the southeastern United States and Bermuda through the Bahamas, Caribbean, Gulf of Mexico, and south to Brazil, this species inhabits shallow coral and rocky reefs, sandy areas surrounding reefs, and occasionally seagrass habitats. It spends much of the day actively searching the substrate and reef structure for crustaceans, mollusks, worms, echinoderms, and other small prey.

Capable of reaching approximately 14 inches at maximum adult size, the Slippery Dick Wrasse is best suited to a spacious marine aquarium with substantial swimming room and a soft sand bed. Its energetic personality and changing coloration make it an appealing display fish for large fish-only aquariums and carefully planned reef systems, although its predatory interest in ornamental invertebrates requires caution.

Quick Care Guide

Care Level: Moderate
Minimum Tank Size: 125 gallons
Temperament: Semi-aggressive
Diet: Carnivore
Reef Safe: With Caution
Region: Western Atlantic – Bermuda and southeastern United States through the Caribbean to Brazil
Scientific Name: Halichoeres bivittatus

Tank Requirements

Provide a spacious aquarium with generous horizontal swimming room, established rockwork, and open areas of fine sand. Caves, ledges, and crevices give the wrasse places to explore and retreat, while open water accommodates its active daytime swimming behavior.

A fine sand bed approximately 2–3 inches deep is important. Like other Halichoeres wrasses, this species buries itself beneath the substrate at night and may dive into the sand when frightened. Avoid coarse crushed coral or sharp substrates that can cause abrasions during repeated burying.

Rockwork should be stable, as larger specimens actively investigate crevices and may disturb loose rubble while hunting. Moderate to strong water movement, excellent oxygenation, and efficient filtration are recommended.

A tightly fitted lid or fine mesh cover is essential. Active wrasses are accomplished jumpers and can escape through surprisingly small openings.

Diet and Feeding

The Slippery Dick Wrasse is a carnivorous benthic predator that naturally consumes a broad range of reef-associated prey, including crabs, mollusks, polychaete worms, sea urchins, brittle stars, and occasionally small fish.

Offer a varied captive diet including mysis shrimp, enriched brine shrimp, krill, chopped shrimp, clam, mussel, squid, and other appropriately sized marine seafood. Quality frozen carnivore blends and high-quality marine pellets can also be incorporated once the fish is feeding confidently.

Feed one to two substantial meals daily, with smaller specimens benefiting from somewhat more frequent feeding. Regular feeding supports good body condition but will not eliminate the wrasse's natural instinct to hunt small animals throughout the aquarium.

Temperament and Tankmates

The Slippery Dick Wrasse is active and generally confident, becoming more assertive as it grows. Mature specimens, particularly terminal males, may show territorial behavior toward other wrasses or similarly shaped fish.

Suitable tankmates include appropriately sized tangs, rabbitfish, angelfish, larger clownfish, robust wrasses, and other peaceful to semi-aggressive marine fish capable of handling its activity level.

Very small, timid, or slow-feeding fish may be intimidated by a large adult. Additional Halichoeres wrasses should be introduced cautiously, especially when aquarium space is limited.

Keeping a single specimen is the simplest arrangement for most home aquariums.

Reef Compatibility

The Slippery Dick Wrasse is reef safe with caution. It does not normally target healthy SPS, LPS, or soft coral tissue, allowing it to be maintained in coral-containing aquariums from that standpoint.

The primary concern is predation on mobile and exposed invertebrates. Ornamental shrimp, small crabs, hermit crabs, snails, brittle stars, small sea urchins, worms, and mollusks may be hunted and consumed, particularly as the wrasse matures.

Its vigorous foraging can also disturb loose rubble or unsecured coral frags near the substrate. It is best suited to a robust reef aquarium where some risk to ornamental invertebrates is acceptable or to a fish-only-with-live-rock system.

Water Parameters

Temperature: 75–80°F
Specific Gravity: 1.024–1.026
pH: 8.1–8.4
Alkalinity: 8–12 dKH

Stable salinity, strong oxygenation, and consistently good water quality are more important than maintaining exact values within these ranges.

Common Considerations

• Large adult size: Maximum length can approach 14 inches, requiring substantial permanent swimming space.

• Sand bed required: Fine sand is important because this species buries itself to sleep and when frightened.

• Predatory toward invertebrates: Shrimp, crabs, snails, mollusks, brittle stars, sea urchins, and worms may become prey.

• Color changes with maturity: Initial-phase fish differ significantly from the green and more intensely patterned terminal males.

• Secure lid essential: This fast, active wrasse is a capable jumper and should always be kept in a tightly covered aquarium.