The Threadfin Butterflyfish (Chaetodon auriga), also known as the Auriga Butterflyfish, is a visually striking marine species celebrated for its distinctive coloration and adaptability. Found throughout the Indo-Pacific region, it is a popular choice among marine aquarists due to its hardiness and vibrant appearance.
Key Information
• Small fish safe: Yes
• Small invert safe: ⚠️ With caution
• Coral safe: ⚠️ With caution
• Minimum tank size: 380 liters (100 gallons)
• Adult size: Up to 23 cm (9 inches)
• Diet: Omnivorous, feeding on a variety of foods including polychaete worms, sea anemones, coral polyps, and algae.
• 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 Threadfin Butterflyfish is distinguished by its striking appearance:
• Body: Predominantly white with diagonal “chevron” markings on the sides.
• Markings: A prominent black vertical band runs through the eye, and the rear edge of the dorsal fin features a black spot with a trailing filament.
• Fins: Bright yellow dorsal and anal fins, with the caudal fin also displaying yellow hues.
Notably, individuals from the Red Sea may lack the dorsal eyespot, showcasing regional variations in appearance.
Natural Habitat and Behavior
In the wild, Threadfin Butterflyfish inhabit a variety of environments, including rich coral reefs, weedy areas, and rubble-covered zones, at depths ranging from 1 to over 35 meters. They can be found singly, in pairs, or in aggregations that roam over large distances in search of food. Their diet primarily consists of polychaete worms, sea anemones, coral polyps, and algae.
Tank Requirements and Water Parameters
To ensure the well-being of the Threadfin Butterflyfish in captivity:
• Minimum Tank Size: A 100-gallon (380 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
Threadfin 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
Threadfin 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, Threadfin Butterflyfish can be a vibrant and rewarding addition to a marine aquarium.