Do you have a drain at the bottom of your pool? If your "ig vinyl liner" is like mine you don't. So all your water gets pulled from the top and the "heavier, cloudy" water is below the skimmer. Take a vacuum head, connect it to the cleaner or skimmer ports and toss the head in the deep end to pull from the bottom. If you have a sand filter add a cup of DE through the skimmer first.

My pool was slightly green & cloudy on Saturday morning because I let it go for a couple days. Did the above (along with 2 gals of bleach) and I was crystal clear the next morning,.