I was hoping you would chime in Borderjumper
and share your experience with them.
They are great little fish. In regards to feeding them flake, I usually put a pinch of flake in the tank and let it submerse so that the flakes are distributed under the water surface, this way it is difficult for them (Anthias) to ingest air from feeding off the surface.
Having said that, maybe you shouldn't feed flake just in case as there are other feeding options for these fish. The don't seem to be too finicky and especially like mysis as well.
Thanks.