I am about to plumb my 2 skimmers and 3 returns. If I make the elbow below the skimmers the lowest spot on the line from pump to skimmer after I take the water down 4 inches below the skimmer for winter, I could just blow out the lines and shop vac them dry correct? I am thinking about doing the same with the returns by putting a Tee at the low spot and a riser level with the concrete deck with a PVC screw plug. Although this may not be cosmetically correct, it would give me great peace of mind knowing my lines are dry. Am I overthinking this, I just cant see how blowing air through completely rids the lines of water and the last thing I want to do is tear up my new concrete if a pipe were to freeze. I would also be able to avoid using antifreeze this way. Any thoughts?