The Midnight Parrotfish (Scarus coelestinus) is a striking marine species native to the tropical western Atlantic Ocean, including the Caribbean Sea, the Bahamas, and the Florida Keys. Renowned for its deep blue to blackish body adorned with lighter blue patches, this species plays a vital role in maintaining the health of coral reef ecosystems.
Key Information
• Small fish safe: ❌ No (may pose a threat due to its size and feeding habits)
• Small invertebrate safe: ❌ No (feeds on corals and other sessile invertebrates)
• Coral safe: ❌ No (actively consumes live corals)
• Minimum tank size: 5,000 litres (1,319 gallons)
• Adult size: Up to 77 cm (30 inches)
• Diet: Herbivorous, primarily feeding on algae; also ingests coral polyps and calcareous substrates
• Be aware of: Requires a very large aquarium due to its size; not suitable for typical home aquariums; can cause significant bio-load due to its feeding habits
Appearance and Colouration
S. coelestinus is characterized by a deep blue to blackish body with lighter blue patches on the head and sides. Notably, a light blue patch is present on the underside of the beak. Unlike other parrotfish species, both juveniles and adults retain similar coloration throughout their life stages. The species can reach lengths of up to 77 cm (30 inches) and weigh up to 7 kg (15.4 pounds).
Natural Habitat and Behaviour
Inhabiting coral reefs and adjacent sandy areas, the Midnight Parrotfish is typically found at depths ranging from 3 to 80 meters. They are often observed in schools, sometimes alongside surgeonfishes, feeding on algae by scraping it off rocks or dead coral with their beak-like teeth. This feeding behavior contributes to the bioerosion of reefs, playing a crucial role in coral health and regeneration.
Aquarium Care
Due to its substantial size and specific dietary needs, the Midnight Parrotfish is not recommended for home aquariums. Successful maintenance requires:
• Tank Size: A minimum of 5,000 litres to accommodate its growth and swimming needs.
• Diet: A continuous supply of natural algae and supplemental feeding with marine-based foods.
• Environment: Robust filtration systems to manage the heavy bio-load and a tank setup that mimics natural reef structures.
Important Considerations
• Reef Compatibility: S. coelestinus is not reef-safe. Its feeding habits can lead to the consumption of live corals and damage to reef structures.
• Behaviour: Generally peaceful towards other large fish but may exhibit territorial behaviour, especially in confined spaces.
• Conservation: While not currently listed as endangered, responsible aquarium practices are essential to prevent overexploitation of wild populations.
Summary
The Midnight Parrotfish (Scarus coelestinus) is a remarkable species that contributes significantly to the health of coral reef ecosystems. Due to its size and specialized care requirements, it is best appreciated in the wild or in large public aquariums designed to accommodate its needs. Hobbyists are encouraged to consider more suitable species for home aquariums to ensure the well-being of both the fish and the reef environment.