What is on this Green Paly?

[jenkyboy]

Hello, I got these green palythoa about a week ago and I noticed these “bubbles” on them today. They are growing near the foot and seem like they are part of the polyp, but I couldn’t find anything about this online. I do not believe it to be bubble algae as I have none other and I did dip and clean these beforehand, but I don’t think they were here a week ago when I received

the frag.

 

[KrisReef]

Photosynthetic sponge looks similar?

 

[jenkyboy]

Photosynthetic sponge looks similar?

I asked on another forum and they said sponge as well so I think you’re correct. Thank you!