My water quality stayed the same for basically since I set it up. So with that, it may be considered stable but I don't know why the other one kicked. I got it home, set him on a high rock (BTA). The lights are T5 nova extreme 2 10k daylight and 2 460nm actinics, maybe it was too much light. He did move to the back of my tank and thats where it stayed. After the few weeks, he did come out to the front and was on a top rock. It looked so nice, he was really open too. Then it moved to the back once again, got near a filter, it was being sucked in a bit so I left the filter off a while. Then turned it on because I needed some filtration in there (I was basically just on and off plugging and unplugging the filter so the anemone didn't get sucked in through the slots on the filter) and then he was a few inches away I think and then I turned it on, maybe went to eat I think, came back and he was in there a bit where his mouth was being stretched, and then he went on the sand foot facing upward. That may have done him in. He may have survived if it wasn't for that filter?
Oh ya, if I would get another BTA in a few months, do any of you guys have perculas that go in a BTA? On that thread, percula isn't listed to go in BTA.