Yes, buy oversized and cut to fit. It is pretty easy with sharp scissors. Just lay it out on the pool and walk along and cut until it fits just inside the pool flat on the water.
It does not "heat" the pool. But, your water temp will go up because you won't start over every morning with heat gain. Without a cover your pool will stay at a midpoint between hi and lo temp. Say 70 degrees if the hi is 80 and the lo is 60. With a solar cover you will cut overnight heat loss by 3-5ish degrees and the pool temp will go up a degree or two every day until it stays closer to the high temp. Same for if you heat the pool, instead of losing say 7 degrees overnight you might only lose 2 or 3 degrees. So, you start with 5 degree warmer water the next day and you build on it daily.
Heating a pool is a process and it moves slowly at first because there is a lot of mass to heat. Water, ground, gunite, etc. But, once you get it all there it doesn't take so much to maintain it. And at that point the biggest loss is overnight heat loss. And a solar cover keeps evaporative heat loss to a minimum.
It does not "heat" the pool. But, your water temp will go up because you won't start over every morning with heat gain. Without a cover your pool will stay at a midpoint between hi and lo temp. Say 70 degrees if the hi is 80 and the lo is 60. With a solar cover you will cut overnight heat loss by 3-5ish degrees and the pool temp will go up a degree or two every day until it stays closer to the high temp. Same for if you heat the pool, instead of losing say 7 degrees overnight you might only lose 2 or 3 degrees. So, you start with 5 degree warmer water the next day and you build on it daily.
Heating a pool is a process and it moves slowly at first because there is a lot of mass to heat. Water, ground, gunite, etc. But, once you get it all there it doesn't take so much to maintain it. And at that point the biggest loss is overnight heat loss. And a solar cover keeps evaporative heat loss to a minimum.
