Swallowtail Angelfish

Genicanthus melanospilos

Also known as Blackspot Angelfish, Spotbreast Angelfish, Japanese Swallowtail Angelfish

SaltwaterFish

Swallowtail Angelfish (Genicanthus melanospilos) — Hectonichus · CC BY-SA 3.0

Care at a glance

Temperature: 72–79°F (22–26°C)
pH: 8.1–8.4
Adult size: 7.1 in (18 cm)
Minimum tank: 106 gal (400 L)
Temperament: Mostly peaceful
Social behavior: Social
Swim level: Middle
Difficulty: Medium
Breeding: Hard
Rarity: Rare
Reef safe: Reef safe
Origin: Western Pacific, from Indonesia to Fiji, north to the Ryukyu Islands, south to Rowley Shoals and New Caledonia
Family: Pomacanthidae

Overview

Swallowtail angelfish are mostly peaceful and, as planktivores, leave corals and clams alone, which makes them reef safe, though they can chase small, docile planktivores, so choose tankmates with that in mind. Keep one male per tank, with multiple females fine in a larger system. Feed small meals of mysis, finely chopped seafood, and spirulina-based foods several times a day.

In the wild

Swallowtail angelfish live on steep western Pacific reef slopes, drop-offs, caves, and boulder bases from about 20 to 45 meters, in areas where coral growth is mixed with open sand. Unlike most Genicanthus, this species splits its time between picking plankton in midwater and foraging down near the bottom. A tank should combine open swimming space with varied rockwork and a bit of sandy bottom to match that dual habit.

Good to know

Genicanthus melanospilos reaches about 18 cm. Males show dark markings across the breast, the pattern behind both the blackspot and spotbreast common names, along with a deeply forked, lyre-shaped tail, while females are paler with different markings and lack the breast patch. It is also sometimes called the Japanese swallowtail angelfish, reflecting part of its range around the Ryukyu Islands.

Did you know

A Palau-based aquaculture operation now produces this species in large captive-bred batches, a real turnaround from years when only a handful of wild-caught individuals would show up in a shipment at a time.