I had something similiar to that, but much more greener.
It had light blue tips as well. I had to do a manual removal which was a PITA.
Nothing I knew would eat those, probably just doesn't appeal anyone's taste buds.
i take a wire brush a scrub scrub scrub and a\occasionally a razor blade to cut.....but since there is a nice size colony on a base rock i guess ill never get rid of them
They dont bother my corals,but they look bad and grow fast
I have them too, ten emeralds in a 125 have a problem keeping up ..
they eat them but slowly..
I have sworn off all hermits but I am entertaining the thought of a couple dozen till these are under control