A few Months ago, I purchased some yellow polyps on a piece of rock. They were doing fantastically well until recently. The polyps all of a sudden began to slowly disappear. Then a few days ago, a discoverd some worms protruding from small holes in the rock and eating the polyps. The worms only come out after the lights have gone off. So far I have seen three worms. The largest one is a dark color with lighter markings. The two smaller ones are light colored with dark markings. Can anyone give me advice on how to get rid of these worms?