The Raccoon Butterflyfish (Chaetodon lunula), also known as the crescent-masked butterflyfish or lunule butterflyfish, is a distinctive marine species recognized for its unique facial markings resembling a raccoon’s mask. This species is native to the Indo-Pacific region, inhabiting coral reefs and lagoons.
Key Information
• Small fish safe: Yes
• Small invert safe: ⚠️ With caution
• Coral safe: ⚠️ With caution
• Minimum tank size: 473 liters (125 gallons)
• Adult size: Up to 20 cm (7.9 inches)
• Diet: Omnivorous, feeding on a variety of benthic invertebrates, algae, and coral polyps.
• Be aware of: May nip at corals and small invertebrates; requires a well-established tank with ample live rock for grazing and hiding; can exhibit territorial behavior, especially towards similar species.
Appearance and Coloration
The Raccoon Butterflyfish is characterized by its striking coloration:
• Body: Yellow-orange hue, darker on the upper half.
• Markings: A black patch around the eyes, with a broad white stripe posterior to it. Two black stripes bordered in yellow extend from the white stripe to the dorsal fin.
These distinctive markings give the fish its common name, as they resemble a raccoon’s facial mask.
Natural Habitat and Behavior
In the wild, Raccoon Butterflyfish are typically found in pairs or small groups in shallow reef flats of lagoons and seaward reefs, at depths up to over 30 meters. Juveniles often inhabit rocky inner reef flats and tide pools. They are primarily nocturnal, feeding mainly on nudibranchs, tubeworm tentacles, and other benthic invertebrates, as well as algae and coral polyps.
Tank Requirements and Water Parameters
To ensure the well-being of the Raccoon Butterflyfish in captivity:
• Minimum Tank Size: A 125-gallon (473 liters) aquarium is recommended to provide sufficient space for swimming and territory establishment.
• Water Parameters:
• Temperature: 24°C – 28°C (75°F – 82°F)
• pH: 8.1 – 8.4
• Specific Gravity: 1.020 – 1.025
• Aquascaping: Incorporate ample live rock to create hiding spots and grazing areas, mimicking their natural reef habitat.
• Lighting: Moderate lighting is suitable.
• Water Movement: Moderate flow to simulate their natural environment.
Maintaining stable water conditions and high water quality is crucial for their health. A mature, well-established aquarium with abundant live rock will support their natural grazing behavior and provide necessary shelter.
Diet and Feeding
Raccoon Butterflyfish are omnivorous, with a diet that includes both plant and animal matter:
• Diet: Offer a varied diet consisting of:
• Marine algae and spirulina
• Mysis shrimp
• Brine shrimp
• High-quality angelfish preparations
• Feeding Frequency: Feed small amounts multiple times daily to meet their nutritional needs.
Providing ample live rock will allow natural grazing behavior, which is beneficial for their health and well-being. Initially, they may be shy and reluctant to eat; offering live or frozen foods can encourage feeding until they become accustomed to prepared foods.
Compatibility and Social Structure
Raccoon Butterflyfish can exhibit territorial behavior, especially towards conspecifics and similar species:
• Social Structure: Best kept singly unless in a very large aquarium where multiple individuals can establish territories.
• Temperament: Generally peaceful towards other species but may become aggressive towards similar-looking fish.
• Compatible Tank Mates: Suitable companions include peaceful community fish such as gobies, blennies, and wrasses. Caution is advised when housing with other butterflyfish or species with similar coloration.
Observing their interactions and providing ample space can help mitigate aggressive behaviors. Due to their territorial nature, they should be housed with non-aggressive tank mates to prevent stress.
Important Considerations
• Reef Compatibility: While often considered reef-safe, individual specimens may nip at corals and clam mantles. Monitoring their behavior is essential, especially in reef setups.
• Acclimation: They may be shy upon introduction but typically become more confident over time.
• Health: Ensure a varied diet and stable water conditions to prevent common health issues.
With proper care and attention to their specific needs, Raccoon Butterflyfish can be a vibrant and rewarding addition to a marine aquarium.