I've read through the posts in the closing topic, but none seems to address my concern. What should the water level be in a closed, plaster in-ground pool? The plaster manufacturer says that plaster should be submerged in water all of the time; but I know that the water level cannot be at the normal, summer mid-tile level during the winter because ice forming at that level will damage the tile. In the past I have drained the pool below the returns to blow out the lines. Then I plugged them and raised the water level to within 18 inches of my mesh, Meco winter safety cover as the manufacturer recommends. But that leaves a bunch of plaster exposed to the air. We have new Pebble Fina plaster this year, so I don't want to damage it over the winter.