I have a 27' round above the ground pool. I don't have a nearby roof to install panels, therefore it will need to be on the ground. I get lots of sun and last summer my water stayed warm. But we are having a lot of rain and cooler nights this summer and the water isn't getting warm at all. I plan to buy a solar cover but I read I should get both in order to keep the water warm. On amazon they have the solar arc, blue wave and kokido. Can anyone give me advice on any of these products?