anemone acting weird

[JE]

so ive had my anemone for a couple of months and it is starting to act up. every 3 days or so for the last few weeks it shrivles up behind the rock work for a few hours. i read that they do this when they are stressed or if there is a spike in the water. my water parameters have been great and i have not had a spike what so ever. i have been dosing kalkawasser consistenly to get my calcium levels up but i have been dosing very little. i have been dosing without a problem the whole time . it is the only thing that i dose but cant figure out what else it can be. any help appreciated....also some of the tentacles are inconsistant with the rest. its a long tentacle anemone, some are normal,some look like a bulbs tentacle and some are just skinny.....

thanks