I had one that was in the sand and wedged under a rock.
My anemone kept moving around and decided to stay where my hawaiian feather duster was, so I was going to move my HFD to another location, but he was attached to the rock.
Later that afternoon I saw that he had came out of the tube and moved under another rock. I got to looking for him one day and did not find him, so I went to pull the empty tube out of my tank and just a piece of the tube broke off. I said oh well i will get the rest next time I do a water change. A week later I thought i saw something in the tube and said naahh just my imagination.
I was doing my water change and guess what there he was in his tube with a very short crown!
now two weeks later his crown is a whole lot prettier!