I asked this same question two weeks ago. The replies were that none were kept in reefs, they were extremely active, semi aggressive, and messy eaters, not to be kept in a small tank (smaller than 120 gallons).
I saw a school of them in a 1200 gallon reef in a hotel lobby. They were shoaling at the top of the tank, and seemed to mind their own business. They were fairly large at about 5-6 inches long. There were no small fish in the tank though, so I don't know how they would act around more peaceful reef fish.