I have a leather that was huge at the LFS. It has not opened its polyps but once in my tank. It has seen to steadily shrink and bounce back for about a week and a half. Well now it has some white edges like it is coming apart. I touched it to see it if would fall apart but it does'nt. You can still see some of the defined edges on it so I am assuming it is still alive. Suggestions or how can I be sure if it is alive?