Never thought about using skimmer socks, but after reading the posts last night decided to give it a try We have been battling what looks like dirt for the past week, putting the sock on the skimmer it is definitely algae. We changed the sock (rinsed them out) atleast 4 times this afternoon and boy was there a lot of green stuff in there each time. So we will add more polyquat and keep the chlorine high.