Koran angels are not reef friendly for a long page of reasons. They get large, will eat fan worms, sponges, lps corals, clam mantles and most soft corals; just to name a few reasons
.
On another note Koran angels change color as they grow up. When full grown Koran angels are not only over a foor in length(about 16"), but no longer sport their blue, black, and white stripe coloration. They become a brownish overall with blue speckles on the body with a bluish outline on the fins and gills. While it is a handsome fish it is definately not nearly as colorful as the juvinile form
.