Description
Melanurus Wrasse (Halichoeres melanurus)
Overview
The Melanurus Wrasse (Halichoeres melanurus), also known as the Tailspot Wrasse or Hoeven’s Wrasse, is a vibrant marine fish from the Labridae family. Native to the Indo-Pacific, it ranges from East Africa to the Tuamotu Islands, north to Japan, and south to the Great Barrier Reef, typically found on coral reefs, rubble zones, and sandy slopes at depths of 1–15 meters. This species displays sexual dichromatism: males are greenish-blue with pink and orange stripes, a distinctive black spot near the tail, and red anal/dorsal fins, while females and juveniles are paler with multiple black spots along the body. Growing to 12 cm in length, it can live 7–10 years with proper care. Its pest-eating habits (e.g., flatworms, pyramid snails) and active personality make it a popular choice for reef aquariums, though its jumping behavior and dietary needs require attention.
Care Requirements
The Melanurus Wrasse is hardy and suitable for intermediate aquarists, thriving in a stable, well-maintained reef tank. Its need for a sandy substrate and secure lid are critical due to its burrowing and jumping tendencies.
Tank Size and Setup
- Minimum Tank Size: 150 liters for a single specimen; 200–300 liters recommended for community tanks to reduce territorial conflicts.
- Aquascaping: Provide a fine sand bed (at least 7.5–10 cm deep) for burrowing, as the fish buries itself at night or when stressed. Include live rock with caves and crevices for hiding and foraging. A tight-fitting lid is essential to prevent jumping, especially during acclimation or stress.
- Lighting: Moderate to high reef lighting enhances its vivid colors; no special requirements beyond standard reef setups.
- Water Flow: Moderate flow (10–20 times tank volume per hour) mimics natural reef currents. Use powerheads or wavemakers for circulation.
- Filtration: Strong filtration with a protein skimmer maintains water quality, crucial for tanks with corals or high bioloads.
Water Parameters
Consistent water quality is vital to prevent stress, color fading, or disease. Test weekly and maintain with regular water changes.
- Temperature 24–28°C Stable; avoid fluctuations >2°C.
- Salinity 30–35 ppt (SG 1.020–1.025) Use a refractometer for precision.
- pH 8.1–8.4 Buffer to maintain alkalinity if needed.
- Alkalinity 8–12 dKH Supports coral health, if present.
- Ammonia/Nitrite 0 ppm Undetectable; toxic at trace levels.
- Nitrate <10 ppm (ideally <5 ppm) Low for reef systems.
- Phosphate <0.03 ppm Prevents algae growth.
- Calcium 400–450 ppm Essential for corals, if applicable.
- Magnesium 1,200–1,400 ppm Stabilizes water chemistry.
Maintenance
Routine care ensures the Melanurus Wrasse remains healthy and active, maintaining its pest-control role and vibrant coloration.
- Acclimation: Drip acclimate over 1–2 hours to adjust to tank conditions. Quarantine for 2–4 weeks to prevent introducing parasites like marine ich.
- Water Changes: Perform 20–30% water changes bi-weekly or 10–15% weekly using RO/DI water mixed with marine salt to control nitrates and replenish trace elements.
- Tank Cleaning: Siphon detritus from the sand bed during water changes to prevent buildup. Use a turkey baster to clear debris from rockwork. The wrasse may eat small pests (e.g., flatworms, bristleworms) but cannot manage heavy infestations.
- Health Monitoring: Monitor for stress (prolonged burrowing, faded colors, reduced appetite) or disease (white spots, erratic swimming). It is hardy but susceptible to ich if water quality declines. Use copper-free treatments and vitamin-enriched foods to enhance immunity and coloration.
Tips: Introduce as one of the last fish to minimize aggression. Ensure a deep sand bed for burrowing and check the tank lid regularly to prevent escapes.
Diet
A carnivore, the Melanurus Wrasse feeds on small crustaceans, worms, and zooplankton in the wild, making it an excellent pest controller (e.g., flatworms, pyramid snails, small bristleworms). A varied, protein-rich diet in captivity supports health and vibrant colors.
Recommended Foods:
- Frozen: Mysis shrimp, brine shrimp, krill, finely chopped seafood (squid, mussel, clam).
- Live: Enriched brine shrimp or copepods, especially for new or picky eaters, though avoid relying on live foods if copepods are needed for other tankmates.
- Prepared: High-quality carnivore pellets or flakes with carotenoids or spirulina to enhance coloration.
Feeding Regimen: Feed 1–2 times daily in small portions to avoid overfeeding and water quality issues. Thaw frozen foods in tank water and soak dry foods in vitamins or brine juice if the fish is reluctant to eat.
Notes: It may consume small beneficial invertebrates (e.g., copepods, micro-snails) alongside pests, so monitor cleanup crew populations. A varied diet (80% meaty foods, 20% pellets/flakes) prevents nutritional deficiencies and reduces aggression.
Behavior and Compatibility
The Melanurus Wrasse is peaceful to semi-aggressive, highly active, and territorial, often patrolling rockwork or burrowing in sand to sleep or de-stress. It may stay buried for days when newly introduced or stressed. Its pest-eating behavior is a boon for reef tanks, but it can chase small fish or invertebrates. Juveniles are shyer, while mature males are bolder and more territorial, especially during spawning displays.
Behavior:
- Active swimmer, foraging among live rock and sand for small invertebrates.
- Burrows in sand at night or when stressed, requiring a deep substrate.
- May clean other fish or exhibit territorial displays (fin flaring, chasing) toward similar species.
Compatibility:
- Reef Safety: Safe with corals (SPS, LPS, soft) but may eat small invertebrates like ornamental shrimp, micro-snails, or fanworms. Monitor cleanup crew populations.
- Tankmates:
- Compatible with peaceful to semi-aggressive fish of similar or larger size, e.g., clownfish, hawkfish, fairy wrasses, flasher wrasses, tangs, or dwarf angelfish. Keep singly or in groups of 5–6 (introduced simultaneously) in tanks >300 liters to reduce aggression.
- Incompatible: Avoid aggressive fish (e.g., large triggers, groupers) that may intimidate it, or very small fish (e.g., gobies, dartfish) that it may harass. Do not house with small ornamental shrimp (cleaner, peppermint) or micro-snails, as they may be eaten.
Notes: In smaller tanks (<200 liters), keep as a solo specimen. Introduce simultaneously with other fish in larger systems to establish territories peacefully.
Reproduction
The Melanurus Wrasse is a protogynous hermaphrodite, with females able to transition to males in the absence of a dominant male. Breeding in captivity is possible but rare in home aquariums due to territorial aggression and the complexity of rearing larvae. Most specimens are wild-caught, as captive breeding is not common commercially.
Breeding Process:
- Pair/Group Formation: In a large tank (300+ liters), introduce multiple juveniles simultaneously; the dominant one becomes male, while others remain female. One male may breed with several females. Aggression often prevents stable pairing.
- Courtship: Males display vibrant colors, fin flaring, and rapid swimming to attract females. Spawning occurs in open water, with females releasing pelagic eggs and males fertilizing them externally.
- Egg Care: Eggs drift in the water column with no parental care. Larvae (2–3 mm at hatch) require live foods like rotifers and copepods for 20–30 days until metamorphosis.
- Challenges: Larval rearing is difficult due to their small size and need for specialized live foods. Aggression between adults often disrupts spawning. Optimal conditions include dim lighting, high oxygen, and temperatures of 24–26°C.
- Recommendation: Breeding is best suited for professional aquaculturists with dedicated setups. Hobbyists should focus on observing natural behaviors like courtship displays in a well-maintained reef tank.
Summary
The Melanurus Wrasse (Halichoeres melanurus) is a hardy, colorful addition to reef aquariums, valued for its pest-eating habits and striking greenish-blue and pink-orange coloration. A 151+ liter tank with a deep sand bed (7.5–10 cm), live rock, and stable water parameters (24–28°C, 30–35 ppt salinity, pH 8.1–8.4) supports its needs. Regular maintenance (20–30% bi-weekly water changes) and a varied carnivorous diet (mysis, brine shrimp, pellets) ensure health and vibrancy. Its peaceful to semi-aggressive nature requires careful tankmate selection (e.g., clownfish, hawkfish; avoid small shrimp or aggressive predators). Breeding is rare in captivity due to aggression and larval rearing challenges. With proper care, it thrives as a functional and visually stunning reef fish.
Picture for illustrative purposes only. Either come in store to view available stock or request pictures to be sent to you.
Please Note: Due to variations within species resulting from age, region, sex, etc., the actual livestock may not look identical to the image. Approximate size range may also vary between individual specimens.
