Something on Zoa (ID Please)

[arash53]

I got some zoas few days ago , I noticed today something bothering one of the Rainbow Hornets polyps , it was very hard to take a picture sorry about the quality but that was the best I could do, and also noticed a kinda strage thing on that polyps like the nest for that bug! ,I was wondring if someone could idetify this bug and tell me how could I kill it.