I cut the top off a plastic 2 liter coke bottle and would place it over the fungia, squirt some food in the top hole and cover it with a small rock.
That way my wrasse wouldnt sneak up and take all the food, two it would give the fungia all the time it needed to consume, and three I would be able to tell that it actually ate something. My wrasse was smart enough to wait till I got far from the tank before going for the food. He was pretty efficient at it.
They show results quickly when feeding them well.
Good Luck