I ended last season with the liner sagging quite a bit. About 4 inches down from the edge, and about 4 ft wide section. I simply closed the pool and said I'll worry about it later. As I started opening the pool this week, I've noticed there is a lot of water behind the liner. Any recommendations on how to get it out? I dont have any special pumps or anything. I have the one I use for on top of the cover. Could I maybe use siphon method? Not so excited about getting a mouthful of that water though. Other options? Once the water is out and when the weather is warmer I'll see if I can stretch the liner back into place but not very hopeful. 4in sag seems like a lot. Liner is otherwise in good shape. Less than 5 years old.