Help ID this. Friend or Foe?

[4n2xtacy]

I've noticed this on my blue star polyp for about 2months now, last night, when I got back from work, I noticed they now had a mouth and im not totally sure but it also looked like there was something inside it. They seem to be getting bigger by the day too. This morning the mouths have opened even wider. What are these things, are they friend or Foe, eggs or sponges. The darker pictures were from last night while the bright picture is this morning when the light came on.

 

[James M]

Sponges. They’re harmless filter feeders but gsp are irritated by them. I would pull them off

 

[LiveWire]

+1 Sponges