Hello all. We closed our pool this year with a merlin solid safety cover with pump. This will be our first winter with this on lol. My only question is, should the center of the cover be sagging or have a shallow low spot? Im assuming its either natural or done to channel the water to the pump itself. Everything is installed perfectly to the T and all straps and anchors are tight and secure. Like i said this is our first safety cover so im still learning 