Pulsing Xenia Vs Zooanthid

[fvlewg65]

I “had” a small Zooanthid frag in my tank, it had been doing fine for the last 6 months and growing nicely. I added a Pulsing Xenia & a conch and a week later the Zooanthid is decimated. I put the two about 12” apart, around the Zooanthid is a Star Polop and a mushroom, but they seem to be fine. Is this a common problem that I wasn’t aware of? How far away should the Pulsing Xenia be from anything else? What else would you recommend?