Over the last few days of hot weather and with a little help from the pool heater, our water temp. was able to get up to about 86. However, the next few days are supposed to be around 70. Can i leave the cover on for a few days without taking it off or do i need to take it off periodically? I don't want to peel the cover back on Thursday and my numbers be out of whack or have messed up water. (not sure that would even happen) I also don't want to let the temp. drop back into the lower 70's by leaving the cover off (pretty sure that would happen) .