Do zoas shed?

I bought a small cluster of Zoas about a month ago. They are doing very well. In the past week its growth had accelerated. I counted 6 new polyps just on the front.(cant see the back and dont want to bother it) but today i noticed that there was some brown thin lining coming off the polyps. i used a 1ml pipette(i have an unlimited amount of them at the lab so i bring them home for my chemicals ) ) to blast some water over them to see if the brown liner came loose and it did. It was the shape of the polyps top. So my question is this the polyp "shedding" or is it something else. I know I know pictures would help but the lens on my camera wont get the small stuff in my tank :/ also not buying a new $300 lens.

Water Par:
Sal 1.026
Nitrite 0
Nitrates 0
Amm 0
pH- 8.2

 

I imagine zoanthids expell waste just like a lot of corals. I have never seen a zoanthid shed but I have not kept a lot.

Bump for perhaps some that has or knows.