its growing under the left side of my Jason Fox Turbinaria. I thought at first it was a acan that some how started growing. But Its hard. Its about the size of a dime, tubular and not a connected circle, its like a single coil of a spring. short tentacles come out the top open end of the coil ( you can see one in the pics). It sends out a mucus type web that extends 6 inches or more touching several corals and then retracts the mucus web back in. Not sure how to upload video, I have one but says wrong format. I have a mp4.