Swallowtail Angelfish-male

The Swallowtail Angelfish, *Genicanthus semifasciatus*, is a captivating and active addition to the marine aquarium. Unlike many other angelfish species, the Swallowtail Angelfish is generally considered reef-safe, making it a popular choice for mixed reef tanks. Males and females exhibit distinct colorations, with males displaying a more vibrant yellow and black pattern, while females are typically a more subdued yellow with less prominent markings. This species is known for its graceful swimming and peaceful demeanor, though they can be territorial towards conspecifics or similar-looking fish.

A minimum tank size of 70 gallons is recommended to provide ample swimming space and rockwork for grazing and hiding. They thrive in a well-established aquarium with plenty of live rock, which provides natural food sources and shelter. The Swallowtail Angelfish is a planktivore in the wild, feeding on zooplankton and algae. In the aquarium, their diet should consist of a variety of high-quality marine foods, including Spirulina, marine algae, mysis shrimp, brine shrimp, and angelfish-specific preparations. They will also graze on algae in the tank.

Swallowtail Angelfish can reach a size of approximately 7 inches in the aquarium. While they are hermaphroditic, breeding in captivity is very challenging. Due to the distinct sexual dimorphism, it is possible to distinguish between males and females. Introducing a male and female together may result in pairing, but successful spawning and rearing of fry are rarely achieved in home aquariums.

Quick Facts

• Scientific Name: Genicanthus melanospilos
• Care Level: Intermediate
• Temperament: Peaceful
• Diet: Omnivore
• Reef Compatibility: Reef Safe
• Region of Origin: Indo-Pacific
• Maximum Adult Size: 9"
• Recommended Tank Size: 70 gallons