A skimmer sock is a nylon cloth that is placed on each of your skimmer baskets. They have an elastic band that is looped over the top of the skimmer basket to hold it in place. As water runs through the skimmer sock prior to going to the filter, debris, oils, and many particles in the water are trapped. This helps keep your filter cleaner much longer and reduces backwash cycles.
Skimmer socks can be washed out a few times and reused before throwing them away. However, we put a fresh skimmer sock on each skimmer during every visit. We feel it is more sanitary.
Below is a picture of a very clear pool. In the picture is a skimmer basket with a skimmer sock we are about to change. To the right is a new skimmer sock we are about to put on the skimmer basket. It is amazing to see how dirty a skimmer sock gets on a pool that looks very clean to begin with. And the dirty skimmer sock is only ONE WEEK old. This is why we use and highly recommend skimmer socks.