I know the MI's are sort of their own class, but are they grouped with Angels? LA sells them grouped in with their Tangs ...?
Quote from LA...
It is the only member of the family Zanclidae, and a very close relative of the Tangs or Surgeonfish. One of the most widespread fish, it can be found throughout the Indian Ocean, Red Sea, and all of the tropical Pacific. Wild specimens can attain a length of 7 inches, but 4 inches is more likely in the aquarium. The Moorish Idol tends to be very peaceful. Due to its size, schooling nature, and need for swimming space, it requires a large aquarium of at least 125 gallons.