Masked Swallowtail Angelfish (Genicanthus semifasciatus)

The Masked Swallowtail Angelfish is also known as the Japanese Angelfish and reside in the northwest Pacific Ocean from southern Japan to the Philippines. They inhabit rocky reefs and are often seen in small groups or harems consisting of one male and several females. Masked Swallowtail Angelfish, like others of the genus (Genicanthus) exhibit dramatic sexual dimorphism where females differ in coloration from males. Females have a cream to white color chest, which gradually changes to yellow along the top of the dorsal, with a dramatic black band over the eye and at the base and along the caudal fin. Males have a bright yellow-orange face that continues horizontally down the side of the fish, with narrow black vertical bars running the length of the fish to the caudal peduncle.

A well-established 125-gallon aquarium or larger will provide enough swimming space to accommodate this species, with lots of hiding places. An exception to most angelfish, the Masked Swallowtail Angelfish will make a good reef dweller, and will not nip at stony and soft corals (sessile invertebrates).

The diet of the Masked Swallowtail Angelfish should include meaty foods with supplemental algae in the form of a high-quality angelfish preparations, enriched mysis shrimp, and enriched brine shrimp.

Approximate Purchase size: Small: 1" to 2-1/4"; Medium 2-1/4" to 3-1/2"; Large 3-1/2" to 5"

Care details

• Temperature: 72 - 78° F
• dKH: 8 - 12
• Specific Gravity: 1.021-1.025
• Diet: Plankton Eater and Omnivore