Is this a type of algae or mold?


Well-known member
Nov 8, 2015
Boston, MA
My water got cloudy this week and I noticed my grids needed backwashing. I took it apart and cleaned. I also added a bunch of shock. Water is nice and clear but on the bottom of the pool there is a white cotton like substance growing all over. It literally looks like a darker white like cotton. I guess I gotta SLAM but curious what it is?