This anemone is starting to p*ss me off.

.
Thank's for the video by the way.
Let me just think out loud a little. The tentacles are quite long. Long enough that if it was a gig, we would consider it healthy. But, the tentacles are quite thick and blunt. At that length, I would expect the tentacles of a gig to be thinner and pointed. There clearly are colored verracue but in the second set of pictures there doesn't seem to be a defined column like I would expect to see on any carpet.
Think of this. Disregard the first post with the picture altogether. What if the OP hadn't ask what kind of carpet he had. What if he asked, is this a carpet or H. magnifica and just showed the first two pics and the video? Mags have verrucae, but they are "supposed" to be the same color as the column. If I knew that mags could have colored verrucae different than their column, I might think that this anemone is a mag with short tentacles.
He said the foot is attached the vertical surface of the rock(which doesn't rule out gig). The tentacles are thick and clubby even though they are quite long (for a carpet anyway) and they have a dark tentacle shaft with a lighter tip.
I am not saying that this
is a mag, but I think that it might be worthy of consideration. Perhaps a purple based mag where the base has faded more than the verrucae?
I would expect to see tentacles that were that long look more like this:
I don't know, I have seen too many anemones lately where pictures just aren't giving me enough information for a positive ID. I wish I could go seem them in person. #1 for a positive ID and #2 because they are really cool anemones.