tube nem a no-show

[reef bound]

We have a beautiful pink tube anemone that has not ventured out for 2 days now. All parameters are good, no other strange things going on in the tank. It hasn't shown any signs of distress in the days leading up to this, but this is indeed odd for it. How long should we give it before we call a time of death. We're worried about decaying anemone. Any thoughts?