I could not zoom in but look up/google Pyramidal Snail and see if these may be them. Not a Coral pest but definitely a Clam and larger Snail pest. Also take a look at Vermatid Snails.
My Wrasses, especially the one in my Avatar love to eat them. I occasionally take the cutters to those in my tank that are bothering corals or easy to access and the Wrasses will follow me around and eat the Snail once de-shelled or exposed.