Pool Covers really do help retain heat in your pool, keep dirt and leaves out, and reduce chemical use. The floating type is however, quite a handful to manage, and you really need a roller system to retract it. The best covers are the ones that are integral to the pool and automatically retract.
If you add a new pool heater, many councils now require you to have a pool cover. It is essential with heat pumps and recommended with gas heaters.
In most pools, the Pooled Energy system will automatically adjust the sanitiser level between times you have the cover on and off, but please understand that the adjustment may take a little time. when you remove the cover, let the pool rest at least a few minutes before leaping in, just in case there is any build-up under the cover.