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Rock Beauty

(Holacanthus tricolor)

Rock Beauty
  • Reef SafetyReef Safe with Caution
  • Care LevelAdvanced
  • TemperamentSemi-aggressive
  • Diet TypeOmnivore
  • Role in AquariumShowpiece Fish
Native RangeWestern Atlantic, including the Caribbean Sea, Gulf of Mexico, and Florida
Species Description
Scientific NameHolacanthus tricolor
Common NameRock Beauty
Species GroupAngelfish
Max Fish Length12 in (30 cm)
Min Aquarium Size125 gal (473 L)

Overview

  • Native to the Western Atlantic Ocean, particularly common throughout the Caribbean Sea.
  • Distinctively marked by its vibrant yellow and black coloration, with a striking blue margin around the eyes.
  • Typically inhabits coral reefs and rocky outcroppings, hence the name "Rock Beauty."
  • Popular among advanced marine hobbyists due to its striking appearance and unique behavior.

Feeding

  • Primarily feeds on sponges in the wild, along with tunicates, zoanthids, and algae; considered a specialized feeder.
  • In aquariums, can adapt to diets containing sponge-based preparations, marine algae, spirulina, mysis shrimp, and specially formulated angelfish foods.
  • Important to provide a varied diet to maintain optimal health and coloration.
  • Multiple small feedings per day recommended due to their specialized nutritional needs.

Habitat

  • Found predominantly in coral reef habitats and rocky substrates, typically at depths of about 10 to 300 ft (3-92 m).
  • Prefers aquariums with extensive rockwork for hiding and grazing; use caution with corals, as it eats zoanthids and sponges.
  • Stable water parameters with gentle to moderate currents are crucial for its well-being.
  • Requires ample swimming space along with hiding spots to reduce stress.

Fish Care

  • Optimal water temperature: 72-78°F (22-26°C).
  • Ideal pH level: 8.1–8.4, with specific gravity between 1.025–1.026 (about 33–35 ppt).
  • Very sensitive to water quality; regular water changes and excellent filtration are mandatory.
  • Best suited for experienced aquarists due to dietary requirements and sensitivity to poor conditions.

Compatibility

  • Semi-aggressive; generally compatible with larger, robust species capable of withstanding occasional territorial disputes.
  • Should ideally be the only angelfish in a tank to prevent aggressive interactions and stress.
  • Not recommended to house with passive or timid fish due to its territorial nature.

Aquarium Behavior

  • Active, curious species, often seen exploring rockwork and corals for food.
  • Can exhibit territorial behaviors, especially if space is limited or in the presence of similar species.
  • Providing a large aquarium and ample hiding places helps reduce aggression and stress.

Frequently Asked Questions

What does the Rock Beauty eat?

In the wild it feeds mainly on sponges, along with tunicates, zoanthids and algae. In the aquarium it needs angelfish preparations containing sponge, plus marine algae, spirulina and finely chopped meaty foods.

Is the Rock Beauty reef safe?

Only with caution. It eats sponges and zoanthids and may nip other corals.

Why is the Rock Beauty rated advanced?

Its sponge-based diet makes it hard to keep healthy long term. It is considered difficult.

What size tank does a Rock Beauty need?

At least 125 gallons (473 L), with extensive rockwork for grazing and hiding.

How big does the Rock Beauty get?

Most aquarium specimens stay smaller, but it can reach about 12 in (30 cm) in the wild.

Is the Rock Beauty aggressive?

It is semi-aggressive and is best kept as the only angelfish, with robust tank mates.

Where does the Rock Beauty live?

In the Western Atlantic, from Georgia, Bermuda and the northern Gulf of Mexico to southern Brazil, on rocky reefs, jetties and coral areas.

What does the Rock Beauty look like?

Adults are bright yellow with a large black rear body, and the eyes are edged in blue.

Do juvenile Rock Beauties look different?

Juveniles are mostly yellow with a blue-ringed black spot on the side, which grows into the black patch of the adult. Young fish often shelter near fire coral.

How deep does the Rock Beauty live?

It is usually found at depths of about 10 to 300 ft (3 to 92 m).