Dusky Butterflyfish
2 Photo Gallery
1 Overview
The Dusky Butterflyfish (Chaetodon flavirostris), also called the black butterflyfish, yellow-kiss butterflyfish, or ‘Australian emperor butterfly’ (ๆพณๆดฒๅธ็่ถ) in the trade, is a member of the family Chaetodontidae. Adults are usually seen in pairs, while juveniles are solitary.
Key facts โ Scientific name: Chaetodon flavirostris. Minimum tank: 300 L. Care level: moderate. Salinity: 1.020โ1.025; pH: 8.1โ8.4. Temperament: peaceful. Maximum size: 21 cm. Reef compatibility: not safe (nips corals). Diet: omnivore with a specialized, largely corallivorous tendency. Origin: Australia. Family: Chaetodontidae.
2 Appearance
The Dusky Butterflyfish is moderately difficult to keep, but with care you can raise a healthy, attractive specimen. Native to Australia, it is harder to acclimate than many marine fish because of its specialized diet โ it favors soft and hard corals.
It is easy to recognize: the front of the mouth is white, behind it yellow, and the body is very dark with yellow-tinted fins. Adults typically appear in pairs; juveniles are solitary. Provide a tank of at least 300 L with live rock for hiding and grazing.
3 Care & Husbandry
A newly acquired Dusky Butterflyfish is best quarantined in an acclimation box before joining the display tank. Ideally keep it species-only (all Dusky Butterflyfish); if mixed, reserve a separate zone for it, because faster competitors will out-compete it for food.
Water quality is critical โ keep it clean and stable in pH and temperature (avoid even slight swings). pH 8.1โ8.4, temperature ~25ยฐC, specific gravity 1.020โ1.025. Ammonia and nitrite must read zero; nitrate very low โ so a strong filtration system and protein skimmer are essential. Top off evaporated water regularly. Feed in a feeding basket so food doesn’t hit the sand and foul the water; remove any uneaten food after 15 minutes.
4 Habitat & Tank Requirements
Water quality is paramount. Although care is rated ‘moderate,’ the specialized diet is the real challenge; proper tank setup must not be overlooked.
Requirements: salinity 1.020โ1.025, pH 8.1โ8.4, minimum tank 300 L, max adult size 21 cm, temperature ~25ยฐC. Ammonia and nitrite must be undetectable and nitrate very low, so a good filter and protein skimmer are needed; top off evaporated water routinely.
5 Diet & Feeding
Butterflyfish have very specialized diets โ unlike general omnivores they may feed on algae, crustaceans, or soft invertebrates. The Dusky’s difficulty comes from its preference for soft or hard corals.
A very picky eater; even robust specimens need time to adjust to aquarium feeding. On introduction, dim the lights and leave the fish undisturbed for at least 24 h, then offer live foods; once it starts grabbing food, you’re halfway there. Within days it should relish brine shrimp. Foods to try: bloodworms, chopped clams, minced shrimp, beefheart, small pieces of squid, and flake. Feeding only one or two food types leads to decline, so vary the diet for health.