Schooling fisheas can consist of tangs, damsel or even anthias.......
In fact most chromis are rather peaceful and they can be mix very well... Anthias however depend, for anthias such as dispar, they can be mix almost without problem and they school beautifully. However anthias such as fairy, tri- color or even square anthias must be mix carefully as male are very intorlerant or one another and will fight almost to death. Then for tang, unless you have a 20feet tank or you won't be able to properly mix a school of tang.