If you stop using your cover during the day it will heat all the way to the bottom of the pool. It will also heat the pool better if you leave your pump off during the day. Long story short, You’ll get a lot better heating with the cover off during a nice warm sunny day and retain the heat with the cover on at night.Click to see full answer. Similarly, should I leave my pool cover on during the day?Ideally, you’ll put your solar blanket on whenever the pool is not in use. Daytime is the best time for it to heat up your water, of course, since it relies on the sun. However, keeping it on through the night prevents water and heat loss via evaporation.Subsequently, question is, is it better to cover your pool? No, but winter covers protect your pool from stains, algae growth and poor water balance that could damage pool surfaces. Pool covers block both debris and sunlight, to conserve your winter chemicals and protect soft and shiny surfaces. And a pool safety cover as shown here, keeps your pool safe and looking great. Subsequently, question is, does a pool warm up faster with the cover on or off? Even the more transparent pool covers filter out a good amount of energy going to the pool. If your ambient temperature is decent and there is not much wind, leaving the pool cover off will heat the water faster (and not just heat the cover and the water near it).Can you heat pool with cover on? Fitting a swimming pool cover Without a cover, a lot of heat is lost through evaporation, among other things. The higher the quality of the cover, the less heat is lost. The best result is obtained with a roller shutter with solar slats. These slats absorb the sun’s rays and convert them into heat.