Quick question about anemones

[Conway23]

I've been wondering about when people keep talking about " open/gaping mouth ". What exactly is this classed as?
Reason I ask is because my rainbow Ben isn't bleaching or expelling, but sometimes I notice that it's mouth is open slightly.

 

[Conway23]

Sorry, rainbow nem

 

[LbulletM]

Hahahaha I thought you named him Ben.

 

[saltyfilmfolks]

Ben's a good name.

Do you feed it?

 

[saltyfilmfolks]

Sorry, do you feed Ben?

 

[Conway23]

Yeah, pieces of mussel and shrimp about twice a week. Small amounts