Been searching for an oval inground winter cover to no avail. I have been using a rectangular cover but the excess cover is not ideal and would like to find an oval shape to more closely match the dimensions of my inground pool. However, it seems manufacturers only make oval above-ground pool covers. What’s the difference between the above-ground and inground winter covers? Why couldn’t I just use an above-ground cover and weigh the perimeter down with water bags like an ordinary inground pool cover? Thanks for any info.