What is it and what should I do

[ATC]

So left on vacation for 2 weeks and upon my return I see these guys on my zoa rock I think aptasia but I’m not really sure. If it is what’s my best mode of removal

 

[Zach B]

Aptasia. I have removed frags that had them, scraped off with a razor blade and super glued over the spot but these were easy spots. The rock may be tougher. I'm sure we'll get some good methods of removal

 

[shakacuz]

kalk paste right over them. can even superglue or epoxy over the holes they're in. if you can take out the rock and do this, even better!

 

[Fuzzbutt]

I had some spots of like those. My best, easiest, quickest suggestion is a Peppermint shrimp. Peppermint shrimp love Aptasia.

 

[acshaw80]

Ive had success with using berghia nudis to get rid of aiptasia that was beginning to spread in my tank. They made quick work of it.