It depends on what yuor definition of "large angels" is. Technically, angels of the Genicanthus genus are large angels and are perfectly reef safe. Other large angels of the Chaetodontoplus and Apolemichthis genus are usually coral friendly, but they have a couple issues in terms of hardiness (many perish in home aquariums for whatever reason) and costs (esp. true of the Apolemichthis, some are over $999). Any 'true' large angel that gets over a foot in length, Queens, Blues, Korans, Passers, French, Bluefaces, Emperors, are really, just a matter of time before they get large enough to sample everything in the tank.