Description:

The Bluespot Butterflyfish, scientifically known as Chaetodon plebeius, is a vibrant and somewhat challenging addition to a marine aquarium. Here’s a detailed look:

Description and Appearance:

• Coloration: These fish are striking, with a predominantly yellow body. Their defining feature is the scattering of iridescent blue spots or blotches, particularly on the upper part of their body, which give them their name. They also typically have a vertical black band running through their eye.
• Size: Bluespot Butterflyfish generally reach a maximum size of 10 to 15 cm (4 to 6 inches) in captivity.
• Juvenile vs. Adult: Juveniles have distinct yellow bodies with clear blue spots. As they mature, their coloration remains vibrant, and the blue spots become a defining feature.

Natural Habitat:

• Geographic Range: They are found in the Indo-Pacific region, from the Andaman Sea to Fiji, north to Japan, and south to Australia (including the Great Barrier Reef).
• Environment: They inhabit shallow coral reefs, lagoons, and outer reef slopes, typically at depths of 1 to 14 meters (3 to 46 feet). They show a preference for areas with abundant coral growth and rocky formations.

Care Requirements for the Aquarium:

• Care Level: Moderate to difficult. They can be challenging to acclimate and get feeding, especially for beginners.
• Tank Size: A minimum of 190 liters (50 gallons) is recommended for a single Bluespot Butterflyfish. Larger tanks (e.g., 340 liters / 90 gallons) are better to accommodate their swimming needs and territorial tendencies, especially if keeping them with other fish.
• Aquascape: Provide plenty of live rock with crevices and hiding spots, as well as ample open swimming space.
• Water Parameters:
  • Temperature: 24-27C (75-80F)
  • pH: 8.1-8.4
  • Salinity (Specific Gravity): 1.020-1.025
  • Water Quality: Excellent water quality is crucial. Maintain undetectable ammonia and nitrite, and keep nitrates as low as possible. Good filtration, including a protein skimmer, is essential.
• Water Flow: Moderate water flow is preferred.
• Lifespan: With proper care, they can live for 5 to 8 years in captivity.

Diet and Feeding:

• Specialized Diet: This is the most critical and challenging aspect of keeping Bluespot Butterflyfish. In the wild, adults are obligate corallivores, primarily feeding on the polyps of stony corals, especially Pocillopora and Acropora species. Juveniles have been observed acting as cleaner fish, removing ectoparasites from other fish.
• Captive Diet: Getting them to accept aquarium foods can be very difficult.
  • Attempt a varied diet: High-quality marine-based pellets, frozen or live foods such as mysis shrimp, vitamin-enriched brine shrimp, finely chopped seafood (e.g., clams, mussels, shrimp), and marine algae/seaweed sheets.
  • Encouragement: Some aquarists have success enticing them to eat by offering live stony coral polyps initially, or by stuffing food into coral skeletons or rocks to mimic natural foraging.
  • Grazing: They will also graze on micro and macroalgae growths on live rock.
• Feeding Frequency: Feed small amounts 2-3 times daily, ensuring they consume the food.

Temperament and Compatibility:

• Generally Peaceful: Bluespot Butterflyfish are known for their peaceful temperament, making them suitable for community aquariums.
• Territorial Towards Similar Species: They can become aggressive towards other butterflyfish, especially those with similar patterns or coloration, particularly in smaller tanks. It’s generally best to keep only one Bluespot Butterflyfish unless you have a very large tank and can introduce a confirmed mated pair simultaneously.
• Reef Safe: No, they are NOT reef safe. This is a critical consideration. Due to their natural diet of coral polyps, they will nip at and consume soft corals, stony polyps (especially SPS and LPS corals), ornamental shrimp, tube worms, and possibly anemones. They are best suited for FOWLR (Fish Only With Live Rock) aquariums.
• Tank Mates: Compatible tank mates include other peaceful fish that won’t outcompete them for food or stress them. Examples include:
  • Clownfish
  • Gobies (of different body shapes)
  • Cardinalfish
  • Tangs (ensure ample space)
  • Dwarf angelfish (with caution, as some can be nippy)

Special Considerations:

• Acclimation: They can be very sensitive to initial acclimation. It’s highly recommended to purchase a specimen that is already actively feeding in the store, and if possible, observe it eating before purchase.
• Quarantine: A thorough quarantine period is essential to monitor for diseases and ensure they are eating prepared foods before introducing them to your main display tank.
• Copper Sensitivity: Like many butterflyfish, they can be sensitive to copper-based medications, so use them with caution and only if necessary.

Compatibility Information