I notice that my leather coral have their polypt extended most of the time . However sometimes they will not extend for hours. (usually not a whole day).
Sometimes, leather corals retract. This often happens if they get a nip from a fish, or if they have been brushed up against by your hand in the tank. Or they just do it for no reason that I can find. Mine quite often retract at night.
Leather corals like good water flow and good water quality, and not getting stung by other corals. My anemone adjusted postion the other day and was touching my big sinularia leather, and the leather scrunched up small and has only started expanding a few days after I moved it away from the anemone.
I find the same thing with mine. I have a finger leather, which had a hitchhiker mushroom attached to it when I received it. The mushroom grew out in time, and once touching the leather, the leather would no longer come out again. Mine also go through phases of closing up completely for a day or two.
