Who knew? Apparently you are NEVER supposed to drain a pool completely as it could ruin the liner. And new liners cost big bucks. When I called the pool store today and told them what we had done they were aghast and figured our liner was kaput. Dunzo. The owner even drove over here to check it out himself. After having no water in it since Sunday our pool miraculously maintained its liner and did not shrink - even in this heat. Go figure! Just lucky I guess as a new liner would cost us $5,000.00 and the wait to have one installed is a very long one.