Black Longnose Tang

Also known as the Longnose Surgeonfish or Longnose Unicorn Tang (juvenile stage).
The Black Longnose Tang is a sleek, uniquely shaped surgeonfish known for its elongated snout, smooth profile, and deep charcoal-to-black body coloration. Found throughout the Indo-Pacific, this species is active, graceful, and constantly grazing. Its distinctive long nose allows it to reach algae tucked between rocks, making it an excellent natural grazer for reef tanks. When properly quarantined, this species adapts well to captivity and becomes a strong, hardy addition to larger marine aquariums.

Key Features

Scientific Name: Zebrasoma rostratum
Common Names: Black Longnose Tang, Longnose Surgeonfish, Longnose Tang
Adult Size: 8–10 inches (20–25 cm)
Lifespan: 10–15+ years with proper care
Temperament: Semi-aggressive; territorial toward other tangs
Reef Compatibility: Reef-safe, does not nip corals or invertebrates.
Minimum Tank Size: 180 gallons (larger recommended)
Experience Level: Intermediate to Advanced, requires pristine water and ample swimming space.

Habitat & Tank Requirements

Natural Habitat:
Native to French Polynesia and surrounding Pacific regions, this tang inhabits clear outer reefs, grazing along vertical rock faces and coral slopes.

Tank Environment:

• Large open swimming areas
• Plenty of live rock for grazing
• Moderate to strong water flow
• High oxygen levels
• Stable, mature aquarium required

Water Parameters

• Temperature: 74–80°F (23–27°C)
• Salinity: 1.023–1.025
• pH: 8.1–8.4
• Ammonia/Nitrite: 0 ppm
• Nitrate: <15 ppm
• Alkalinity: 8–12 dKH

Essential Equipment

• Oversized protein skimmer
• Strong circulation pumps
• UV sterilizer for disease reduction
• Reliable auto top-off system
• High-capacity biological filtration
• Regular water changes (10–15% weekly)

Diet & Feeding

Black Longnose Tangs are herbivores that require constant plant-based nutrition.

Recommended Foods

• Nori sheets (green, red, or brown)
• Spirulina-based pellets and flakes
• Frozen herbivore blends
• Marine algae sheets
• Occasional mysis or brine (supplements only)
• Vitamin- or garlic-soaked foods to boost immunity

Feeding Schedule

• Feed 2–3 times daily
• Keep nori available on a clip
• Provide algae-rich diet for long-term health and color

Behavior & Compatibility

Temperament:

Active, alert, and assertive, especially toward other tangs. Peaceful with most non-tang species.

Tank Mates:

Compatible with:

• Wrasses
• Gobies
• Anthias
• Butterflyfish
• Peaceful reef fish

Caution with:

• Other Zebrasoma tangs
• Surgeonfish with similar shape or diet

Avoid:

• Aggressive triggers
• Groupers
• Very small timid fish if aggression becomes territorial

Color & Development

Coloration Characteristics:

• Deep black or charcoal body
• Elongated snout
• Smooth dorsal and anal fin lines
• Sharp white caudal spine
• Soft gradient toward lighter fin edges in some individuals

Color Intensity:

A high-quality herbivore diet ensures rich, stable coloration. Poor water quality or stress may cause dulling.

Size & Growth:

Juveniles start at 2–3 inches and grow steadily, reaching adult size within 2–3 years.

Acclimation & Care Tips

Initial Acclimation:

• Drip acclimate for 45–60 minutes
• Float bag for 15–20 minutes
• Dim lights during introduction
• Provide rockwork hiding spots
• Offer nori immediately

Health Considerations:

Black Longnose Tangs may be prone to:

• Marine ich
• Marine velvet
• HLLE (Head and Lateral Line Erosion) from poor diet or water quality
• Bacterial infections if stressed

Quarantined specimens have significantly improved survival and feeding response.

Signs of a Healthy Specimen:

• Smooth, consistent dark coloration
• Clear, bright eyes
• Strong grazing behavior
• Active swimming
• No spots, lesions, or fin tears
• Steady appetite

Special Considerations

Quarantine is Recommended:

This species is sensitive to parasites and stress during transport. Dr Reef’s quarantine ensures they are:

• Observed for several weeks
• Preventatively treated when necessary
• Stabilized and feeding well
• Adapted to captive conditions

Breeding Potential

Breeding Black Longnose Tangs in home aquariums is extremely rare. They require very large open-water conditions and group-spawning behavior that cannot be reproduced in typical tanks. While they display natural social behaviors, actual spawning is not expected in captivity.

Why Choose a Quarantined Black Longnose Tang?

A fully quarantined specimen offers better long-term success, fewer health issues, stronger feeding habits, and a smoother transition into your display tank, giving you confidence that your new tang will thrive in your reef system.