Id please

[Rubicon]

So I was moving some coral around that was unhappy and I came across this, what is it? Good bad or....? It has some sweepers that come out, it seems to annoy my leather finger, but I had it in a bad place as well so he is not happy at the moment.

[Rubicon]

Not a clue as to what it was, but the leather is much happier with it gone.

[Myka]

It's a tunicate/sponge. I've seen that type quite often in one client's tank, though I've never tried to ID it.