What are these white growths under the live rock?

[187ReefTank]

Good evening. Can anyone identify these white growths under my live rock?

Are they good or bad? Do I need to get rid of them? How if needed?

Thanks!

 

[Patx]

Tunicate ?

 

[EricR]

I would've gone with pineapple sponges as a guess, personally.

 

[BristleWormHater]

100% positive its pineapple sponges. They are harmless filter feeders and usaully go way on their own