Dusky Wrasse - Halichoeres marginatus

Dusky Wrasse (Halichoeres marginatus)

The Dusky Wrasse, Halichoeres marginatus, is a bold, active and attractive marine wrasse, admired for its changing colour pattern, lively swimming behaviour and natural pest-hunting ability. Also known as the Two-Eyed Wrasse, Splendid Rainbow Wrasse or Marginated Wrasse, this species is a larger Halichoeres wrasse that is best suited to mature marine aquariums with good swimming space, established rockwork and a soft sand bed. It can be a useful and eye-catching reef fish, but its adult size, active nature and interest in small invertebrates mean it should be planned carefully.

Common Name:
Dusky Wrasse, Two-Eyed Wrasse, Splendid Rainbow Wrasse, Marginated Wrasse, Margined Wrasse.

Scientific Name (Latin):
Halichoeres marginatus

Maximum Size:
Up to around 18 cm, making it a larger Halichoeres wrasse that needs more space than smaller species such as Yellow Wrasse or Melanurus Wrasse.

Water Type:
Marine

Origin / Natural Habitat:
Found widely across the Indo-Pacific, including the Red Sea, East Africa, Mozambique, the Indian Ocean, southern Japan, Australia, the Great Barrier Reef and parts of the Central Pacific. In the wild, Dusky Wrasse inhabit lagoon reefs and seaward reefs, especially along the upper edges of coral-rich areas. Juveniles may be found on exposed outer reef flats, while adults are usually seen singly or in small loose groups.

Water Parameters:
Temperature: 24–27°C
pH Range: 8.1–8.4
Hardness or Salinity: SG 1.020–1.025

Temperament:
Peaceful to semi-aggressive. Dusky Wrasse are usually manageable with suitable marine fish, but they can become assertive as they mature, especially towards very timid fish, small passive wrasses or similar sand-sleeping wrasses. Best kept with peaceful to moderately robust tank mates that will not be easily intimidated or outcompeted.

Diet:
Carnivorous micro-predator. In the wild, this species feeds on a wide range of small invertebrates and fish eggs. In the aquarium, offer a varied diet including frozen mysis shrimp, enriched brineshrimp, krill, cyclops, copepod-based foods, chopped clam, mussel, prawn and high-quality marine pellets. It may also pick at flatworms, pyramid snails, small worms and other tiny reef pests, although it should not be relied upon as the only pest-control method.

Minimum Tank Size:
A practical minimum of around 400–500 litres is recommended for a single adult specimen, with larger aquariums preferred for long-term success or mixed wrasse communities. Provide mature rockwork, caves, rubble zones, open swimming space and a soft sand bed deep enough for burying.

Behaviour & Activity:
An active daytime wrasse that spends much of its time cruising around rockwork, inspecting crevices and hunting for small foods. Like many Halichoeres wrasses, it will bury itself in the sand at night, when frightened or during the settling period. Newly introduced specimens may hide in the sand for a short time while adjusting. A tight-fitting lid is essential, as wrasses are strong jumpers when startled.

Reef Safe:
Reef Safe
Dusky Wrasse are generally considered safe with corals and do not normally nip coral tissue or clam mantles. However, they may eat small ornamental crustaceans, fan worms, tubeworms, tiny snails, flatworms, pods and other small mobile invertebrates. They are best described as reef safe with caution because they suit coral reef aquariums, but are not ideal where very small ornamental invertebrates are a priority.

Special Requirements or Care Notes:
Best kept in a mature aquarium with a soft sand bed of at least several centimetres so the fish can bury naturally. Avoid bare-bottom systems or sharp, coarse substrate that may damage the fish when it dives into the sand. This species can be sensitive during transport and acclimation, so introduce carefully and monitor feeding closely. Use a secure jump guard, provide plenty of rockwork and avoid adding to systems dominated by aggressive wrasses or very territorial fish.

Suitable for:
Intermediate fishkeepers

Availability:
Occasionally available in the marine aquarium trade / Availability can vary depending on supplier, size, sex, colour phase and import season

All images are a visual representation of the fish you will receive, made to be as accurate as possible. Please note that Mother Nature is a wonderful thing, and variation in patterns and colours will occur — that is part of the unique beauty of these animals.