Sunburst Butterflyfish (Chaetodon kleinii)

The Sunburst Butterflyfish is one of the most underrated fish in the hobby and one of the very few butterflies that genuinely earns the description beginner-friendly. Its golden-yellow body carries a pale front section, a bold dark vertical bar running through the eye, distinctively dark lips, and blue iridescence edging the dorsal, caudal, and anal fins, producing a colour palette that stands out beautifully against reef rockwork under any lighting. Also known as Klein's Butterflyfish, the Orange Butterflyfish, and the Blacklip Butterflyfish, C. kleinii is a not-too-picky feeder, a good shipper, active and intelligent, and one of the most adaptable members of a family that is otherwise notorious for demanding care. For hobbyists who have always wanted a butterflyfish but been put off by the typical challenges of the group, this is the species to start with.

Why we love it

• Considered one of the most durable members of the butterflyfish family, with a strong record in both public and private aquarium systems
• Warm golden-yellow colouration with striking facial markings and iridescent fin edging that pops under reef lighting
• Unlike most butterflyfishes, C. kleinii gets along with others of its own species and can be kept in groups when introduced simultaneously
• Known to consume Aiptasia anemones, making it a useful addition to systems struggling with pest anemone outbreaks
• Active, curious, and intelligent, quickly learns feeding routines and recognizes its keeper

Suggested parameters

• Temperature: 24 to 26°C (75 to 79°F)
• Salinity: 1.025 to 1.026 SG
• pH: 8.1 to 8.4
• Alkalinity: 8 to 10 dKH
• Ammonia/Nitrite: 0
• Nitrate: Under 20 ppm; stable, mature water chemistry is strongly preferred
• Strong oxygenation and efficient filtration recommended; butterflyfishes do best in clean, well-maintained systems

Care and temperament

• Difficulty: Moderate (hardy for a butterflyfish, but still requires a mature system and stable parameters)
• Temperament: Peaceful; can be kept with other butterflyfish of its own and different species, and even alongside moderately assertive species as long as it is introduced to the aquarium first
• Reef safe: With caution (will nip at soft coral polyps, particularly Litophyton and Sarcophyton species, and may consume small ornamental tubeworms; best kept in systems with noxious or less palatable soft coral species, or in fish-only and FOWLR setups; generally leaves LPS and SPS corals alone)
• Minimum tank size: 280 litres (75 gallons) for a single specimen; larger is preferred
• A well-established aquarium with lots of open swimming space, live rock for hiding, and existing algae growth gives this fish the best start

Diet

C. kleinii is considered one of the most adaptable feeders in the butterflyfish family, browsing filamentous algae, zooplankton, and soft coral polyps in the wild; in captivity it typically accepts a wide range of foods readily.

• Frozen mysis shrimp (staple)
• Frozen brine shrimp and enriched artemia
• Marine algae-based frozen foods and spirulina flakes
• Nori and dried seaweed sheets
• Quality omnivore pellets once established
• If reluctant to feed initially, small clams or black mussels on the half-shell placed in the tank will often entice a feeding response; frozen mysis and brine shrimp are typically accepted readily once the fish has settled in
• Feed two to three times daily; multiple small feedings support this active species better than a single large meal

Compatibility and tankmates

• Excellent with tangs, larger wrasses, angelfish, gobies, blennies, dartfish, and most peaceful to moderately assertive reef fish
• One of the few butterflyfishes that can be successfully kept in groups; introduce all individuals simultaneously for the best outcome
• Ideally introduced to the aquarium before any more assertive species; new additions introduced to a tank with an established fish of this species may experience minor bullying
• Not suitable for reef tanks with prized soft corals, ornamental tubeworms, or Aiptasia that the keeper intends to preserve
• Avoid aggressive triggerfish, large puffers, and dominant species that may stress this peaceful fish

Health and acclimation notes

As with all butterflyfishes, the Sunburst Butterfly benefits from a well-established system with stable parameters, and quarantine before introduction to a display tank is always encouraged. This species is notably more tolerant of the stress of shipping and acclimation than most of its family, but slow drip acclimation remains best practice. Watch for common marine parasites such as ich and marine velvet during the first few weeks, and ensure the fish is feeding actively within the first few days of introduction. A varied, protein-rich diet fed frequently is the single most important factor in long-term health and colouration.

What you are buying

• You will receive: 1 Sunburst Butterflyfish (Chaetodon kleinii)
• Colouration can vary slightly between individuals and collection regions; the dark lip marking, vertical eye bar, and golden body are consistent identifying features across the species

Slow acclimation is recommended. Quarantine before introduction to your display is encouraged.