Strange growth on GSP

[Por914]

Today while feeding I found this hard growth inside my gsp coral. It’s kind of hard and stayed all together when I picked it out. I am not sure what it is and could find anything on it so I just picked out for now. Any help would be appreciated.

 

[JGT]

Bubble algae. Toss it.

 

[Por914]

Bubble algae. Toss it.

Thanks, I didn’t know that bubble algae was hard.