Hermit Crab Anemone Help!!!

[MombasaLionfish]

My hermit crabs anemone was fine this morning and when I got home this evening I noticed a weird white gash in the front of it. It also won't open up. Please help.

 

[BloopFish]

My guess is that it got smashed against a rock while the hermit crab is moving - not sure what you should be doing to treat it though.

 

[MombasaLionfish]

It opened up today.

 

[MombasaLionfish]

I have water getting ready for a water change hopefully that will help. Any other suggestions?