They seem to. I generally turn them inside out, shake them off (outside the pool area of course), stick my hand inside and swish them both in a clean bucket of water. Then I empty the bucket, refill and really swish and squeeze and pick off any remaining stuff. Then I let them air dry for a least a day - this really seems to be the key to having them continue to work. I've thought about adding a bit of bleach to the last soak, but instead I'm going to throw them in the wash with my Pool Rover bag at some point. So far, they seem to hold up pretty well.

I'm rotating 3 sets now (started with 2 before I started using the socks full time).