Tibicen Keyhole Angelfish

Also known as the Keyhole Angelfish or Melas Angelfish

The Tibicen Keyhole Angelfish is a stunning and highly sought-after large angelfish native to the Western Pacific Ocean. This magnificent species displays dramatic coloration with a deep black to dark blue body adorned with a distinctive white vertical bar across the midsection and striking white accents on the face and fins. The common name “Keyhole” refers to the characteristic white marking pattern. This rare and beautiful angelfish is prized for its bold appearance and commanding presence, making it a prestigious centerpiece fish for large marine aquariums.

Key Features

• Scientific Name: Centropyge tibicen
• Common Names: Tibicen Keyhole Angelfish, Keyhole Angelfish, Melas Angelfish, Tibicen Angelfish
• Adult Size: 7–8 inches (18–20 cm)
• Lifespan: 10–15+ years with proper care
• Temperament: Semi-aggressive; moderately territorial
• Reef Compatibility: Not reef-safe – will nip at corals and sessile invertebrates
• Minimum Tank Size: 75 gallons (100+ gallons preferred)
• Experience Level: Intermediate to Advanced – requires stable conditions and careful acclimation

Habitat & Tank Requirements

Natural Habitat: Found on outer reef slopes, drop-offs, and coral-rich areas at depths of 50–200 feet throughout the Western Pacific, including Indonesia, Philippines, Papua New Guinea, and the Great Barrier Reef. Inhabits caves and crevices in deeper reef zones, typically as solitary individuals or in small harems. This is a deepwater species that requires careful collection and acclimation.

Tank Environment:

• Abundant live rock with multiple caves, overhangs, and hiding spots
• Complex rockwork structure for territory establishment and security
• Moderate to ample swimming space
• Well-established aquarium (4–6 months minimum for stability)
• Moderate to strong water flow with calmer refuge areas
• Subdued to moderate lighting (deepwater species adaptation)

Water Parameters:

• Temperature: 72–78°F (22–26°C)
• Salinity: 1.023–1.025 specific gravity
• pH: 8.1–8.4
• Ammonia/Nitrite: 0 ppm
• Nitrate: <20 ppm (lower preferred)
• Alkalinity: 8–12 dKH
• Dissolved Oxygen: High levels (important for deepwater species)

Essential Equipment:

• Quality protein skimmer
• Efficient biological and mechanical filtration
• Moderate to strong water circulation
• Regular water changes (15–20% biweekly minimum)
• UV sterilizer (highly recommended for disease prevention with deepwater species)

Diet & Feeding

Tibicen Keyhole Angelfish are omnivores requiring a varied diet rich in both meaty foods and marine algae for optimal health and coloration.

Recommended Foods:

• Plant Matter: Nori sheets, spirulina, marine macro algae, dried seaweed preparations (30–40% of diet)
• Frozen Foods: Mysis shrimp, enriched brine shrimp, cyclops, finely chopped krill, marine fish flesh, angelfish formula preparations
• Pellets/Flakes: High-quality marine angelfish pellets, spirulina-enriched formulas, herbivore pellets, color-enhancing foods
• Prepared Mixes: Angelfish blends containing sponge material, marine cuisine, Formula Two, plankton preparations
• Natural Grazing: Live rock with established microalgae and film algae growth
• Supplements: Vitamin C-enriched foods, garlic-based supplements for immune support, omega fatty acids

Feeding Schedule:

• Feed 3–4 times daily in smaller portions (deepwater species often have higher metabolisms)
• Provide nori or seaweed sheets clipped to tank glass for continuous grazing
• Rotate food types to ensure complete nutrition
• Allow natural algae to grow on some rocks for supplemental grazing
• May take several days to begin feeding after introduction (patience required)

Tank Mates:

• Compatible with: Semi-aggressive tangs, most wrasses, clownfish, damselfish, dottybacks, larger gobies, blennies, cardinalfish, chromis
• Caution with: Other dwarf angelfish (only in tanks 100+ gallons with multiple territories); very peaceful fish may be intimidated; slow-moving species
• Avoid: Multiple Centropyge species in tanks under 100 gallons, extremely peaceful fish (firefish, dartfish), other Tibicen Angels, very aggressive species that may bully it

Reef Compatibility:

• Not reef-safe: Will nip at various corals and invertebrates
• Known to pick at LPS corals (favia, favites, brain corals, acans)
• Will damage soft corals and zoanthids
• Can nip at clam mantles
• May consume coral polyps and flesh
• Particularly destructive to certain SPS polyps
• May pick at feather dusters and Christmas tree worms
• Best suited for FOWLR (Fish Only With Live Rock) systems
• Rare individuals may leave some corals alone, but this cannot be predicted or relied upon

Acclimation & Care Tips

Initial Acclimation:

1. Extended drip acclimation over 2–4 hours (deepwater species require slow, careful acclimation)
2. Dim tank lights for first 48–72 hours minimum
3. Provide ample secure hiding spots
4. Minimize all activity and disturbances around tank for first week
5. May take 3–7 days to begin feeding (patience essential)
6. Do not chase or attempt to force viewing if hiding
7. Introduce to peaceful to semi-aggressive community for best results

Health Considerations:

• Moderately delicate due to deepwater collection origins
• Highly susceptible to marine ich (Cryptocaryon irritans) and velvet (Amyloodinium ocellatum)
• Sensitive to poor water quality and rapid parameter fluctuations
• Stress from decompression and shipping makes them vulnerable to disease
• Can develop lateral line erosion (HLLE) with inadequate diet or poor water conditions
• Prone to weight loss if not eating properly or outcompeted for food
• Quarantine for 6–8 weeks minimum before display tank introduction (absolutely essential)
• UV sterilization highly beneficial for disease prevention

Encouraging Feeding:

• Offer food near hiding spots initially
• Use highly aromatic foods (garlic-soaked mysis, black worms)
• Feed when lights are dimmed or during evening
• Try live brine shrimp or live black worms to trigger feeding response
• Be very patient; some deepwater specimens take week or more to eat
• Once feeding begins, gradually diversify diet

Deepwater Acclimation Challenges:

• Collection from 50–200 feet creates significant stress
• Decompression can cause internal issues
• More sensitive than shallow-water dwarf angels initially
• Require extra time and patience during acclimation
• Choose specimens that have been held by retailer for 2–4 weeks minimum
• Quarantined specimens have dramatically higher survival rates

Color & Development

Adult Coloration: Tibicen Keyhole Angelfish display striking, distinctive patterns:

• Body: Deep black to dark blue-black base color
• Vertical Bar: Bold white vertical bar across midsection (the “keyhole” marking – most distinctive feature)
• Face: White to pale blue markings around mouth and chin area
• Pectoral Fins: Bright white to pale yellow
• Other Fins: Dark with white to pale blue edging
• Eye Area: Dark with subtle blue accents
• Overall appearance is dramatic high-contrast pattern

Color Variations: Some regional and individual variation exists:

• Body color ranges from pure black to dark blue-black
• White bar width and intensity varies between individuals
• Some show more extensive white facial markings
• Pectoral fins can be pure white to yellowish-white
• Western Pacific specimens may show slight pattern differences

Tank Size Importance:

• 75 gallons: Absolute minimum for single specimen
• 100+ gallons: Better for long-term success and reduced aggression
• 125+ gallons: Allows for potential multiple dwarf angelfish with caution
• Larger tanks significantly reduce territorial issues
• More swimming space helps with active personality

Personality and Interaction:

• Often develop bold, interactive personalities once established
• Can become quite confident and front-of-tank fish
• May recognize keeper and approach glass at feeding time
• More engaging than many shy dwarf angel species
• Initial shyness gives way to assertive behavior

Breeding in Aquariums

Spawning Behavior:

• Rarely spawns in home aquariums
• Possible with established pairs in large systems
• Spawning typically occurs at dusk
• Eggs are pelagic (released into water column)
• No parental care provided
• Larval rearing extremely difficult and not practical for most hobbyists
• Requires specialized facilities, rotifers, copepods, and extensive expertise

Quarantine Protocol

Why Quarantine is Absolutely Essential: Tibicen Keyhole Angelfish are deepwater species that are highly vulnerable to stress and parasitic infections. Their collection difficulty, rarity, and high cost make quarantine critical for protecting your investment and ensuring long-term success.

Our Quarantine Process:

• Observation Period: 6–8 weeks minimum (longer for delicate deepwater specimens)
• Decompression Recovery: Extended time for deepwater species to stabilize from collection stress
• Parasite Prevention: Comprehensive prophylactic treatment for marine ich, velvet, flukes, and internal parasites
• Dietary Conditioning: Patient training to accept varied prepared foods including essential plant matter
• Stress Reduction: Quiet, dimly lit environment with ample hiding spots for recovery
• Feeding Establishment: Ensuring consistent, eager feeding response before sale (critical for deepwater species)
• Health Monitoring: Daily observation for any signs of parasites, infection, stress, or feeding issues
• Acclimation Training: Gradual adjustment to standard aquarium parameters from deep water
• Behavioral Assessment: Observation of aggression levels, shyness, and compatibility potential
• Weight Maintenance: Multiple daily feedings to ensure robust body condition

Why Choose a Quarantined Tibicen Keyhole Angelfish?

Purchasing a properly quarantined Tibicen Keyhole Angelfish, with 6-8 weeks of care, ensures it recovers from deep-water collection stress, is parasite-free, and confidently eats a varied diet, greatly increasing its chances of thriving in your aquarium.