green star polyps not opening

[v80s]

I have a piece of green star polyp and it hasn't oppened in several days. It looks okay not falling off rock or anything it just isn't oppening. Is this cause for alarm?

 

[DJ88©]

[moved]

 

[SCR]

They do that , just give it sometime.

 

[v80s]

is there anything you can do to promote them to open more often? I noticed that they were always open at the lfs where I bought them.