Solar cover questions

[wingertom]

I live in the far northern part of California. I have found that in my 18 AG my solar cover that it not only holds heat in durrng the day but that there is an aprox. 10 degrees difference the first 6 incher or so and @ about 18 inches, where I take my test water from, So it not only keeps my pool warmer durring the day but tends to heat it too. (evaperation happens day or night) My cover says specifily to make sure and put the bubbles down for the best results. I almost forgot I get sunlight only about 4 or 5 hours a day, my swimming season is around June through september or October. My pool temp went from about 71 degrees to about 85 with in a month.