I lose about 3 with my cover..versus 5 without..then it warms to the point I don't even bother with a cover..
90! We got a little too scared of the cold front and rain yesterday. We figured the cold, 30mph north wind and rain would cool the pool a lot but it was 87 last night and solar bumped it to 90 already! Dang, the pool is kinda hot. :-D
My HP50HA needs a 240v, 20a breaker, it draws max 12 amps. It would add 1 degree every 6.2ish hours. It would make heat pretty efficiently at 65+ degrees. So, plus 4 degrees per day, open the cover on low wind, sunny days to help more.
Thanks for the summary.