I am using skimmer socks for the first time and I LOVE them! I wish that I would have found them 4 years ago. Daily I wash the nastiness out of each sock and put it back into the skimmer basket with a rock to weigh it down. When I look at my beautiful water, I wonder where all this sandy film comes from off the surface of the water, but I am just thrilled because of how it has drastically reduced the amount we backwash now. After 3 weeks they are looking pretty ragged, so I too will change them monthly. What a cheap way to save the filter and DE!