Yellow Belly Regal Angelfish (Pygoplites diacanthus)

Description

The Yellow Belly Regal Angelfish (Pygoplites diacanthus) is one of the most stunning and highly sought-after marine fish in the hobby, instantly recognizable by its vibrant, repeating vertical bands of electric blue/white and yellow/orange. The 'Yellow Belly' designation refers to variants collected from the Red Sea, Maldives, and parts of the Indian Ocean, which feature a distinctly yellow or orange-yellow chest and ventral region.

This medium-sized Angelfish brings unparalleled color to a well-established reef or fish-only aquarium. It is an Expert Only species with specific care requirements. Successfully keeping a Regal Angelfish requires a large, stable environment and ensuring the fish is actively eating a varied diet upon introduction. While generally semi-aggressive, they are often shy and can be outcompeted for food by more boisterous tank mates.

Care Information

Aquarium Requirements

• Tank Size: A minimum of 125 gallons is required to provide ample swimming space and a stable environment.
• Water Conditions: Stability is paramount.
  • Temperature: 72°F – 78°F
  • Salinity: 1.020 – 1.025 specific gravity (sg) or 30-34 ppt
  • pH: 8.1 – 8.4
  • Alkalinity (dKH): 8 – 12
• Aquascape: The tank must have plenty of live rock to provide hiding places and ample surface area for grazing. A well-established rockscape is critical for this species.

Diet and Feeding

The most significant challenge with the Regal Angelfish is getting it to feed consistently in captivity. They must be offered a varied and comprehensive omnivorous diet multiple times per day.

• Primary Diet: Mysis shrimp, enriched brine shrimp, and chopped fresh seafood (e.g., clam, shrimp, squid).
• Herbivore Content: Daily offerings of marine algae, spirulina, and high-quality angelfish preparations containing sponge material are essential.
• Acclimation: New specimens often take time to accept frozen and prepared foods. Providing live rock or starting with live foods may encourage feeding.

Temperament and Compatibility

• Tank Mates: Choose tank mates carefully. While semi-aggressive, the Regal Angelfish is often shy and passive compared to other angels. Avoid overly aggressive fish like large triggerfish or predatory groupers.
• Reef Safety: The Regal Angelfish is not fully reef-safe and should be kept with caution in a reef setup. It may nip at soft corals, clam mantles, and certain LPS corals, but is generally safe with invertebrates and SPS corals.

Quarantine (QT) Notes

A quarantine protocol is highly recommended. Regal Angelfish are sensitive to rapid changes in water quality and high ammonia levels. QT should be performed in a spacious, stable system, ideally with some cured live rock to encourage natural grazing and maintain feeding during observation.