Rock Beauty Care Guide
Holacanthus tricolor is a Western Atlantic marine angelfish with a sponge-dominated diet that makes it challenging to keep; IUCN Least Concern.
Compiled by Aquairi from published sources · Published · Updated
Overview
Holacanthus tricolor, the Rock beauty, is a marine angelfish of the family Pomacanthidae, originally described by Marcus Elieser Bloch in 1795 (as Chaetodon tricolor) from Brazil. Adults are yellow on the head and anterior body with a black region covering most of the flank. FishBase records a maximum total length of about 35 cm.
Taxonomy
- Family: Pomacanthidae
- Genus: Holacanthus
- Scientific name: Holacanthus tricolor
- Described by: Bloch, 1795 (as Chaetodon tricolor)
Habitat
It occurs in the Western Atlantic from Georgia (USA), Bermuda and the northern Gulf of Mexico south to Santa Catarina, Brazil. The species is reef-associated and found at depths of about 3-92 m, typically 3-35 m, on rock jetties, rocky reefs and coral areas. Juveniles often associate with fire corals.
Tank requirements
- Minimum tank volume: 1500 L
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Lifespan: 15-20 years
- Water type: marine (saltwater)
Diet
Adults feed largely on sponges, but also take corals, zoantharians, bryozoans, gorgonians, tunicates and algae. FishBase lists a trophic level of about 3.0. The heavy reliance on sponges makes adequate nutrition in captivity demanding.
Compatibility
A large semi-aggressive angelfish that is not reef-safe; sponges and corals are at risk. Unlike some related angelfishes, it does not act as a cleaner fish. Other large angels are best avoided, while robust tankmates suit very large systems.
Conservation status
IUCN Red List: Least Concern (assessed 2009). FishBase notes minor commercial fisheries and aquarium-trade use, and documents reports of ciguatera poisoning associated with the species.
Holacanthus tricolor (Rock Beauty): Breeding Guide
Overview
Holacanthus tricolor is a large marine angelfish of the family Pomacanthidae from the Western Atlantic, ranging from Georgia and Bermuda through the Gulf of Mexico to Santa Catarina in Brazil. According to FishBase it reaches about 35 cm and occurs at depths of 3 to 92 m, usually 3 to 35 m. Its sponge-dominated diet and large adult size mean that reproduction occurs only in the open ocean, not in tanks.
Sexing
External sexing is unreliable. FishBase notes that protogyny (female-to-male sex change) has been proposed for this species but awaits confirmation. Functional pairs are recognised mainly through behaviour rather than visible dimorphism.
Spawning Behavior & Trigger
Wikipedia reports that adults are normally encountered as long-term monogamous pairs. During spawning the pair ascends together in the water column with abdomens close, releasing eggs and milt simultaneously into open water as a broadcast (pelagic) spawn.
Egg & Fry Care
The transparent eggs are pelagic and hatch after roughly 15 to 20 hours. A female may release between 25,000 and 75,000 eggs in an evening and up to about 10 million in a season. The early larvae carry a large yolk sac and lack functional eyes, gut or fins, with settlement after about 3 to 4 weeks. There is no parental care.
Common Challenges
The combination of open-water spawning, a long planktonic larval stage and an obligate sponge diet makes home breeding impractical. Wikipedia notes the trade was supplied exclusively by wild-caught specimens until captive breeding of this species appeared only in the 2020s, at specialist facilities rather than home tanks.