These super rare fish are one of the holy grails of angelfish. They come from the deeper waters around Hawaii and are rarely exported, making them desired and not cheap.
As juveniles these fish are all white with a black vertical band on the face.As they get a little older a vertical black band over the base of the caudal fin forms. When they mature the sexual dimorphism gets visible, with females developing a more complex black mask and yellow pelvic fins. Males get orange pelvic fins, a yellow to orange face and broad orange rim on the dorsal and anal fin. The caudal fin gets all black and develops long filaments.
To see their natural behaviour they can best be kept as a pair.
Like all other angelfish it's hermphroditic and the most dominant fish will turn into a male when there is no other male around.
These fish are quite peaceful but be careful combining them with fish a lot smaller or larger and other (dwarf)angelfishes.
In nature, Geniacanthus are plankton feeders. This makes them the the most reef safe members of the angelfish family and very desired for reef tanks.
Offer them a varied diet of enriched live and frozen food and once settled they usually should accept dry food was well, so you can offer them high quality pellets and chopped meaty foods.