Genicanthus is a genus of marine angelfishes in the family Pomacanthidae. Known commonly as swallowtail or lyretail angelfish, these fishes are so-named for the distinctive shape of their tailfins. This genus of angels, in comparison to the other species found in hobby aquaria, are a good choice for beginners as they do not get nearly as large as some of the others. Another unique attribute is that swallowtail Angels will tolerate each other and can be kept in pairs or as a single male with a harem, though it is typically best to add them to a tank at the same time. If added on by one, the angel which is added first may become aggressively territorial towards any new additions. Unlike others in the Pomocanthidae family, the angelfish in the Genicanthus species are generally considered to b