Dascyllus melanurus (Four-Stripe Damselfish / Blacktail Humbug)
• Small fish safe: ❌Caution due to aggressive behaviour
• Small invert safe: ✅ Yes
• Coral safe: ✅ Yes
• Minimum tank size: 113 liters (30 gallons) or larger
• Adult size: Up to 10 cm (4 inches)
• Diet: Omnivorous (varied diet including algae, planktonic crustaceans, and prepared aquarium foods)
• Be aware of: Territorial and aggressive, especially as they mature. Best kept singly or in groups in appropriately sized tanks with similarly aggressive or larger tank mates. Juveniles are more social but become more dominant as they age.
Four-Stripe Damselfish (Dascyllus melanurus) – A Striking Yet Territorial Marine Species
The Four-Stripe Damselfish, also known as the Blacktail Humbug, is a visually striking species recognized for its distinctive black and white banding and robust nature. While its hardiness makes it appealing to aquarists, its territorial and aggressive behavior necessitates careful consideration when adding it to a community tank.
Appearance and Coloration
The Four-Stripe Damselfish is characterized by:
• Coloration: A white body with three prominent black vertical bands and a fourth black band ending at the tail.
• Body Shape: Deep-bodied with a laterally compressed form, contributing to its distinctive appearance.
• Size: Reaches up to 10 cm (4 inches) in length.
This bold coloration and compact body make it a standout addition to marine aquariums.
Natural Habitat and Behavior
Native to the western Pacific Ocean, including regions such as Indonesia, the Philippines, New Guinea, and the northern Great Barrier Reef of Australia, Four-Stripe Damselfish are typically found in:
• Habitat: Associated with isolated coral heads in sheltered inshore habitats, often near Acropora species.
• Depth Range: Found at depths down to 10 meters (33 feet).
• Social Structure: Juveniles often form schools, while adults become more solitary and highly territorial.
In the wild, juveniles exhibit social behavior, forming groups, while adults establish and defend territories aggressively.
Tank Requirements and Water Parameters
To accommodate the Four-Stripe Damselfish’s needs:
• Minimum Tank Size: 113 liters (30 gallons) or larger to provide ample space and reduce territorial aggression.
• Aquascape: Incorporate abundant live rock formations to create hiding spots and establish territories.
• Water Parameters:
• Temperature: 24–27°C (75–81°F)
• pH: 8.1–8.4
• Salinity: Specific gravity of 1.020–1.025
Maintaining stable water conditions with regular monitoring is essential for their health.
Diet and Feeding
Four-Stripe Damselfish are omnivorous with a hearty appetite:
• In the Wild: Feed on fish eggs, crustacean larvae, algae, ostracods, amphipods, copepods, and tunicates.
• In Captivity: Accept a variety of foods, including:
• High-quality marine flakes and pellets (preferably vitamin-enriched)
• Frozen or live foods such as mysis shrimp and brine shrimp
• Algae-based foods to supplement their diet
Feeding once or twice daily with a varied diet will help maintain their health and coloration.
Compatibility and Tank Mates
Due to their aggressive and territorial nature, careful selection of tank mates is crucial:
• Suitable Tank Mates: Other aggressive or semi-aggressive species of similar or larger size, such as certain wrasses, tangs, or triggerfish.
• Invertebrates: Generally reef-safe, posing no threat to corals or most invertebrates.
Avoid Housing With:
• Passive or timid fish, which may be harassed or bullied.
• Other damselfish species, unless in a very large tank with ample hiding spots.
If keeping multiple Four-Stripe Damselfish, it’s advisable to introduce them simultaneously to minimize territorial disputes.
Breeding and Reproduction
Breeding Four-Stripe Damselfish in captivity is possible:
• Spawning: They are substrate spawners, with females depositing adhesive eggs onto flat surfaces such as rocks or aquarium glass.
• Parental Care: Males typically guard and aerate the eggs until they hatch.
Providing flat surfaces and maintaining excellent water quality can encourage breeding behavior.
Health and Disease Considerations
Four-Stripe Damselfish are hardy and resilient, but they can be susceptible to common marine diseases if stressed:
• Marine Ich (Cryptocaryon irritans): Can occur under poor water conditions or high stress levels.
• Bacterial Infections: May result from injuries due to aggressive interactions.