My anemone will sometimes close up into a ball and flip over and over in the water current in one area. He protects his mouth with his tentacles and i have to stick him down onto rocks every-time. This time when i went to out him on a rock i noticed it had some white stuff on the foot (not really sure what part of the anemone it was because it was a ball) the white stuff looked like feta cheese with little green strings in it. Is this poop? What is it? Thanks