This has been our first pool summer and we've learned a lot along the way. We finally got rid of our wedding cake stairs after learning thru 3 different SLAM's that they were harboring algae that seemed impossible to get rid of! Last Wednesday I began bringing the FC level down from SLAM value of 26. I'm now around 10, which is a little on the high side of my range, I know. So far things have gone very well. Each morning I tend to see some clumps that look like this picture, so I've been running the dolphin and it does a great job cleaning it up. I jumped in a little while ago to get a closer look, it's a brownish yellowish color and is only on the bottom, nothing on the walls. After more research on here, is it possible that it's dead algae still falling from the SLAM last week? Could it also be pollen from the oak tree that's close to the pool?