Foxface eating corals

[hillegom]

I have not heard of this before. My foxface of 2 weeks, is eating my green star polyps. They seldom come out anymore. Just the purple leathery base is there and he nibbles only on the "bumps" So in the morning, the GSP start to open and some have tenacles missing, others are totaly gone.
Not only that but he also ate my white sponge from the back wall, up high under an overhang where there wasn't much light.
I thought that he would be happy with 2 types of macro algae that I have in the 50 gal tank. It isn't all gone yet. Everyone also gets flakes one day, pellets another and frozen a diff day.
Anyone else ever heard of a foxface that likes sponges and coral?
If this keeps up he might have to go,lol