I had this hitch hiker come in a while back. It started off around the size of a pea on a small rock, it grew to about 2 inches then moved off the rock onto the sand. Another one started growing on the rock where the original one was and did the same. Now I have four of them with the largest being four inches. I've looked around but cannot find anything on it. At first I thought it was some kind of carpet anemone but they don't have the big month in the middle. Any help would be appreciated.