need an ID

I agree it does look like a paly, but I know for a fact that this rock hasnt had any on it in atleast 15yrs. It had been in an establish FOWLR tank for 15yrs prior to me getting it. If it is a paly, then its odd for it to just show since I dont have any of those, and they were never there before. They just kinda showed up. It is possible they were dormant since the rock was collected from fiji over 15yrs ago and kept under inadecute lighting during that time, and since adding it to my tank, I have much better lighting then they are use to.

 

Yes. We put a rock that had been sitting in our sump for several years into our 46 gallon hex. Lo and behold, within a few months, we had a rock covered in palys.

 

Personally i would say this is Zoanthus sp. not a paly anyways they all belong to the same family (zoanthidae) and all the care requirements are the same so it really doesnt matter. It's either Zoanthus sp. or Protopalythoa sp..