Just a thought for you guys, I was just doing my tank maintenance on my sebae anemone tank. I call it that because it has killed about every mushroom, ric, zoe's, torch coral, fox coral, candy cane coral, etc. All I have left in there with it is a hugh hammer coral that is still out of its reach, and a few polyps. I found 1 little mushroom hiding around the corner from the anemone. Mind you I have had to remove a bunch of corals from this tank, besides the ones it killed.
So if you want to keep your corals healthy I would return the anemone. If you want to end up with and anemone tank, keep it but be aware that it will get rid of all your corals for you and you will have to get it a much bigger tank in the future.
First picture is when I first got it, 2 yrs ago. Last picture was taken about 6 mo's ago. It has grown a lot even since that picture.