What is this?

[Robert Doolan]

Hello,
I have these brown bubbles appearing on my rock. Can anyone help me identify them and how I could remove them. I tired getting them off during a water change but that didn’t work.
Thanks

 

[MombasaLionfish]

If it is bubble algae then I'm pretty sure peppermint shrimp will eat it.

 

[MombasaLionfish]

But I dont think thats bubble algae.