Thank you for the quick response i will try and get a better picture when i have a moment. If your guess is correct though what is the process for removal and methods to prevent reappearing?
The frag had been in for months before it ahowrd up and its only visible in this location. When it started the zoas werent bothered by it and it atarted to show signs of establishing a footing off the frag and onto the the surrrounding rock and i thought tank is only 8? Months old i have zero experience maybe im finally seeing a frag grow.
Anyways should i set it on fire? What should i do? Is this a matter of water chemestry needed or a simple pest removal?
If those are hydroids, it's nothing to do with water chemistry (aside from "can support life", and you need to manually remove them. Scraping them off and smothering the spot in putty or superglue is a good bet.