I've been successfully using the BBB method for over a month now. Recently, I went away for a few days and when I returned I noticed that there was some algae starting to form on the bottom of my pool. I shocked the pool and then noticed that the Sight Glass on the Filter has what looks to be green algae covering the bottom half of the glass. I backwashed for a couple of minutes and this didn't clear it up.
Is this a sign that there's something wrong with my filter or will the shocking process clean this part of the filter as well as the pool?