I have a pebbletec pool. I am in the middle of shocking for mustard algae. This is the 5th night that I am trying to keep FC at 24. I notice tonight that there are a lot of white specks at the bottom of the pool. I cannot tell if some of the pebbles came loose or got bleached out because I had put so much chlorine in the pool since Monday night. All I know is that there are a lot of white specks on the bottom of the pool that I have neve seen before. Had this happen to anyone else?