Help! White spriggy growths on corals rock

[alaind`]

Trying to determine what these things are, and what to do about them? very small, but appear to be propagating. I attempted to literally throw my credit card at them, but they were unphased. Thanks in advance!

 

[KrisReef]

Get a new chip reader!

 

[EeyoreIsMySpiritAnimal]

Bryozoans. Harmless

 

[KrisReef]

I was going to guess what @Erin1971Texas said, or perhaps an unknown algae? Is that Florida live rock?

 

[alaind`]

Thanks! I think I’ll pull a bunch tomorrow to see if I can keep it in check. The rock has been in this system for 7 years, relocated to our house about 7 months ago. Just noticed this growth on one rock yesterday. 2nd owner, not 100% sure where the rock came from. The growth has probably been there a little while i’m guessing.

 

[EeyoreIsMySpiritAnimal]

Thanks! I think I’ll pull a bunch tomorrow to see if I can keep it in check. The rock has been in this system for 7 years, relocated to our house about 7 months ago. Just noticed this growth on one rock yesterday. 2nd owner, not 100% sure where the rock came from. The growth has probably been there a little while i’m guessing.

I would have guessed from the pic that this was recently added dry rock.