Quote Originally Posted by FormerBromineUser View Post
That might be it. I also get the gunk even when I have had no swimmers in the pool for over a week. It seems so strange that it doesn't occur in-pool at the waterline.
I did have it show up on the steps one time after a guest got in the pool after slathering up with a bunch of sunscreen, but other than that it only shows up in the skimmers. It has never appeared on the liner.