Encyclopaedia

FishMarineAdvanced

Watanabe's Angelfish

Genicanthus watanabei

An awe-inspiring deep-reef swimmer, the Watanabe's Angelfish exhibits highly contrasting stripes in males. It is fully reef-safe, actively feeding on passing plankton, and prone to jumping if unsecured.

Taxonomy

Class:Actinopteri

Order:Perciformes

Family:Pomacanthidae

Genus:Genicanthus

Species:Genicanthus watanabei

Check out Watanabe's Angelfish on Atlarium

PracticeRecognition quizzesPhotos, names, origins, and puzzles to review Atlas species.Open quizzes

Water Temperature

22 - 26 °C

pH Value

8.1 - 8.4

Water type

Marine

Tank level

Surface

Adult size

15 cm

Minimum tank volume

>= 500 L

Minimum group

>= 1

15 - 25 dGH

8 - 12 dKH

Species description

Geographical Origin and Habitat: Tropical and subtropical Indo-Pacific, from Taiwan and the Ryukyu Islands to the Cook and Tuamotu Islands. Inhabits current-swept outer reef slopes at depths of 21 to 81 meters. They inhabit deep drop-offs and steep seaward slopes subject to strong oceanic currents.

Taxonomy and Morphology: Member of the family Pomacanthidae. Reaches a maximum length of 15 cm. Features a slender, compressed body with a deeply forked swallowtail caudal fin. Sequential protogynous hermaphrodite. Their body is sleek and adapted for swimming actively against moderate-to-strong currents.

Social Behavior: Peaceful and highly active water-column swimmer. Forages constantly in currents in small haremic groups. Highly prone to jumping when startled. They live in social harems with a single male guarding several females in the water column.

Coloration and Sexual Dimorphism: Striking sexual dichromatism. Males are pale blue with horizontal black stripes on the lower body and a yellow stripe near the anal fin. Females are uniform pale blue with black margins on the fins and head. The dramatic difference in pattern between males and females makes them highly prized by aquarists.

Care, breeding and tankmates

Aquarium Setup: Requires an aquarium of at least 500 liters with vast open swimming space and strong, well-distributed currents. A tight-fitting lid is mandatory as they are exceptional jumpers. Provide a large aquarium with robust water flow to mimic their deep-reef drop-off habitat.

Diet and Feeding: Carnivore/Planktivore. Feeds exclusively on zooplankton in the wild. In captivity, feed 3–4 times daily with mysis, brine shrimp, calanus, copepods, and high-quality pellets. Feed a varied diet rich in planktonic items like calanus, mysis, and high-quality marine flakes.

Water Quality: Demands stable parameters. Temperature 22–26°C, pH 8.1–8.4, salinity SG 1.020–1.025, GH 15–25, and KH 8–12. High biological load requires robust filtration and skimming. Maintain high oxygen levels and pristine water parameters to ensure the long-term health of this species.

Compatibility and Cohabitation: Very peaceful toward other reef fish. Completely reef-safe; it will not nip at corals or sessile invertebrates. Excellent in pairs or small harems. Excellent reef compatibility; they generally do not nip at corals or sessile invertebrates.

Aquarium Breeding: Undocumented in home aquariums. Broadcast spawners releasing pelagic eggs in the wild. Spawning requires deep tanks and specific lighting cycles, making home breeding extremely rare.

Risks and Diseases: High incidence of swim bladder issues if decompression was poorly managed during capture. Susceptible to marine ich (Cryptocaryon) if stressed. Pay close attention to swim bladder issues, which can sometimes occur in deep-water collected specimens.

Geographic Origin and Distribution

Tropical and subtropical Indo-Pacific, from Taiwan and the Ryukyu Islands to the Cook and Tuamotu Islands. Inhabits current-swept outer reef slopes at depths of 21 to 81 meters. They inhabit deep drop-offs and steep seaward slopes subject to strong oceanic currents.

Origin

Tropical oceans and reefsEast Asia

Fish profile

Temperament: Peaceful
Diet: Carnivore
Sex ratio: Harem
Feeding frequency: THREE_FOUR_DAILY
Bioload: The bioload is moderate. Efficient biological filtration is required. Regular water changes keep nitrates low.
Flow: Strong
Jump risk: Yes
Reproduction: Oviparous
Compatibility & tankmates: Reef safe
Tank level: Top

FishBase

Window to the official scientific data of the species

Data synced on: 06/15/2026

Scientific Parameters & Models

Trophic level: 3.4 ± 0.45 se
Resilience: Medium (1.4 - 4.4 years)
Phylogenetic uniqueness (PD50): 0.501
Bayesian Length-Weight: a = 0.0302, b = 2.89

Image gallery

Licensed images linked to the species or, when marked, to the closest representative taxon.

Related species

Recommendations grouped by close relatives, companion choices, and similar care.

Variants and close relatives

Same atlas type, nearby scientific identity, genus, or family.

Blackspot Angelfish

Genicanthus melanospilos

Species description

Care, breeding and tankmates

Geographic Origin and Distribution

Origin

Fish profile

Scientific Parameters & Models

Image gallery

Related species

Variants and close relatives

Blackspot Angelfish

Lamarck's angelfish

Ornate Angelfish

Zebra angelfish

Japanese swallowtail angelfish

Masked Angelfish

Colin's Angelfish

Fisher's Angelfish

African flameback angelfish

Barred Angelfish

Clarion Angelfish

Flameback Angelfish

Joculator Angelfish

Limbaugh's angelfish

Yellowfin Angelfish

Resplendent Angelfish

Recommended companions

Armed Snapping Shrimp

Antillean hermit crab

Arethusa Hermit Crab

Bahia Cleaner Shrimp

Boschma's hermit crab

Cook's hermit crab

Danai's hermit crab

De Man's Hermit Crab

Feather Duster Worm

Lysmata prima shrimp

African snapping shrimp

Anker's Cleaner Shrimp

Blood-spotted Hermit Crab

Bouvier's snapping shrimp

Camel shrimp

Chapin's Hermit Crab

Similar care

Dusky Angelfish

Japanese Pygmy Angelfish

Blue Angelfish

Passer Angelfish

Debelius' angelfish

Downing's Shrimpgoby

Shepard's angelfish

Royal Dottyback

Asfur angelfish

Black-axil Chromis

Multicolor Angelfish

Blue Chromis

Bandit Angelfish

Peppermint Angelfish

Singapore Angelfish

Blue assessor