Yellow Pyramid Butterflyfish 

Also known as Pyramid Butterflyfish, Zoster Butterflyfish

The Yellow Pyramid Butterflyfish is a beautiful and relatively hardy species displaying bright yellow coloration with distinctive diagonal black lines forming a pyramid-like pattern. This peaceful and social butterflyfish is one of the more adaptable species and can even be kept in small groups, making it an excellent choice for butterflyfish enthusiasts.

Key Features

• Scientific Name: Hemitaurichthys polylepis
• Common Names: Yellow Pyramid Butterflyfish, Pyramid Butterflyfish, Masked Boarfish
• Adult Size: Up to 7 inches
• Lifespan: 5-7 years with proper care
• Temperament: Peaceful and social; can be kept in groups
• Reef Compatibility: Generally reef safe; primarily planktivorous
• Minimum Tank Size: 125 gallons minimum
• Experience Level: Moderate; easier than many butterflyfish species

Habitat & Tank Requirements

• Tank Environment: Provide substantial open swimming areas with moderate rockwork for shelter. This planktivorous species spends considerable time in open water, especially when kept in groups. Benefits from good water flow.
• Water Parameters:
  • Temperature: 72-78°F (22-26°C)
  • Salinity: 1.020-1.025
  • pH: 8.1-8.4
  • Good water quality is important
• Equipment Recommendations:
  • Quality protein skimmer
  • Efficient filtration system
  • Moderate to strong water circulation These maintain the clean conditions this active species prefers.

Diet & Feeding 

Yellow Pyramid Butterflyfish are planktivores requiring frequent feedings. Recommended foods include:

• Staples: High-quality marine pellets, vitamin-enriched flake foods
• Frozen Foods: Mysis shrimp, brine shrimp, cyclops, copepods, finely chopped seafood
• Live Foods: Live brine shrimp, copepods (helpful during acclimation)
• Feeding Frequency: 2-3 times daily
• Special Note: Readily accepts prepared foods; easier to feed than coral-feeding butterflyfish

Social Structure & Group Dynamics

• Can Be Kept in Groups: Unlike most butterflyfish, naturally schools in the wild
• Peaceful Nature: Non-aggressive toward conspecifics and other species
• Introduce Simultaneously: Add entire group together for best results
• Group Size: 3-5 individuals create impressive displays in larger tanks

Notes & Considerations

• One of the few butterflyfish that can be successfully kept in groups without aggression.
• More reef-safe than most butterflyfish due to planktivorous diet; rarely nips corals.
• Bright yellow coloration with a diagonal pyramid pattern is visually striking.
• Very active swimmers that utilize the full water column.
• Generally peaceful toward all tankmates.
• Secure aquarium lid recommended; can jump if startled.
• Groups create synchronized swimming behavior similar to Schooling Bannerfish.
• Hardier and more adaptable than obligate coral-feeding species.
• Does not require live rock for grazing like many butterflyfish.
• Excellent choice for fish-only, FOWLR, or peaceful reef aquariums.
• Pacific origin; moderately available in the trade.

Why Choose a Quarantined Yellow Pyramid Butterflyfish? 

Purchasing a quarantined specimen from us means you’re starting with a healthier, better-acclimated fish. All fish are observed, treated as needed, and conditioned to accept prepared foods before sale, giving you a stronger chance of long-term success with this vibrant and social species.