ID please

[paul.o]

These were given to me by someone closing their tank, not sure if i'm keeping them as I don't want anything that spreads too fast and these look like they might.

 

[ReeferHD]

zoanthids, not sure of the trade name of these specific ones but generally they can spread quickly if conditions are favorable, but you'd be fine with putting them on their own rock or even leaving the frag on the sand bed.