I have a zoa frag that's been in the tank about a month. I dipped before introducing it to the tank along with other frags. Nothing came off. In the last week I could see crud building up at one end of the colony. Today the encrustation was larger, so I pulled it out and scraped of quite a bit of the crud. Beneath it was a small calcareous tube.. (you know what I'm thinking!).
I dipped the frag.. and this came out. Maybe just under 1/2". What is it?
I dipped the frag.. and this came out. Maybe just under 1/2". What is it?