Weird substance on my zoa frag??

[Richie1898]

Just added these guys last Tuesday and everything’s been perfect. Did a 40% water change on Wednesday and all levels appear to be fine. Came home from work and one of my zoas (blue ******) has this weird brown/black string? Any help?? Or ideas

 

[BayouReefer]

I don’t think it’s a real issue probably just got blown there by pumps take a turkey baster or pipet and blow it back off