I was cleaning the tank in my wife`s office when I noticed this growing out of large group of Zoas that have been in the tank for about 9 months. I took my long tweezers to see if I could move the polyps that are near what ever this is and as soon as the tweezers were near it pulled the tentacles back in and retracted below the top of the Zoas? Any ideas what this is and is it OK to leave it or do I need to remove it. Thanks for the help!



