Threebanded Butterflyfish

Threebanded Butterflyfish

The Threebanded Butterflyfish (Chaetodon humeralis) is the Eastern Pacific's counterpart to the more familiar banded butterflyfish — a clean silvery-white body crossed by dark bands, including the characteristic eye-band and a broad bar across the rear. Hardy and adaptable for a butterflyfish, it feeds on small invertebrates rather than depending on living coral, which makes it one of the more practical butterflyfish to keep. Coming from cooler Eastern Pacific waters, it appreciates slightly lower temperatures.

It is a handsome, robust fish for the keeper wanting a butterflyfish without the extreme difficulty of obligate coral-feeders.

Natural Habitat & Origin

Chaetodon humeralis is found in the Eastern Pacific, from the Gulf of California south along the coast of Central and South America, where it lives on rocky reefs and over sandy areas, often in pairs or small groups, foraging for small invertebrates. Its productive, cooler home waters shape its preferences.

In the aquarium it appreciates plenty of live rock for foraging and shelter, in a calm community with cooler, stable water.

Care Requirements

Maintain stable marine conditions: salinity around 1.024–1.026, pH 8.1–8.4, and a temperature toward the cooler end of the range, around 22–25°C (72–77°F), reflecting its origin. Reaching about 17 cm (6.5 inches), it suits a tank of around 280 litres (about 75 US gallons) or more with ample rockwork. It is hardier and more adaptable than most butterflyfish.

Diet & Feeding

This butterflyfish is an omnivore, feeding in the wild on small invertebrates, worms and some algae rather than living coral. It usually adapts well to captivity: offer a varied diet of frozen mysis and brine shrimp, marine preparations and foods with marine algae content. Feed several small meals a day to keep it in good condition.

Behavior & Temperament

It is a peaceful, active fish that mixes well in a calm community and can be kept singly or as a pair. It rarely troubles other fish and spends much of its time foraging over the rockwork. Avoid housing it with aggressive species that will outcompete it or keep it hidden.

Tank Mates

Good companions are other peaceful marine fish — tangs, peaceful wrasses, anthias, cardinalfish and similar — that tolerate cooler water. In a reef it is relatively well behaved for a butterflyfish, but because it may nip coral polyps or invertebrates it is best described as reef-safe with caution, and is safest with hardy corals or in fish-focused systems.

Breeding

Chaetodon humeralis is a pelagic spawner with planktonic larvae and is not bred in the home aquarium. Trade specimens are wild-collected.

Common Health Issues

The Threebanded Butterflyfish is among the hardier butterflyfish but, like all marine fish, is susceptible to marine ich (Cryptocaryon irritans) and marine velvet (Amyloodinium ocellatum), particularly when stressed or newly imported. Quarantine new arrivals, keep water quality stable, and offer a varied diet. Given a peaceful tank and slightly cooler water, it is one of the more approachable and dependable butterflyfish for an intermediate keeper.