Mine eat anything...mysis, rods, flakes, pellets, cyclopeeze. They don't care! But they both do the chewing up and spitting out thing also. Mine only seem to do that with food in chunks that are 2 big for their liking. Perhaps mine are spoiled and don't feel like chewing their food.
I have 2, bought at separate times as females. After about a month, one of them started developing the long male spike on the dorsal. He never changed colors to the reddish shade that I've seen pics of though. But, started growing at a substantially faster rate than the female. Not sure if that is related to the sex or if that fish just likes to eat more.
I would imagine my male is about 5" long and a brilliant orange with purple accents. He occasionally does this thing where he swims sideways around the other fish in my tank, which appears to be a 'hey, look how big I am' move...but, he has never nipped or be aggressive to anybody.