It sounds like you keep your solar cover on during the daytime hours or you keep a very high concentration of Chlorine in your pool. (am I correct on either?)
Solar covers (unfortunately for them are named wrong), should only be on your pool at night to stop heat from escaping, they do not help in attracting heat into your pool during the day, rather, a lot of the heat that could be gained gets bounced off the cover and back into the air.
Proper use of a solar cover means rolling it up during the day and allowing the light to filter through your water, bouncing off the floor and walls of the pool, that way, the floor/wall absorbs heat and puts it into the water, the water will also absorb a small amount from the rays travelling through it, but since water is almost transparent it is very minimal.
The cover should be rolled up and covered, many people sew a few bedsheets together and make a clip on cover to place over the roller, white bed sheets reflect the sunlight better that a blue cover, helping your cover last even longer.
I have a medium grade solar cover that is still like new after 2.5 years (and it stays on teh reel over the winter), mind you, my chlorine level is extremely low thanks to this forum and that probably has a lot to do with it. I do not follow proper solar cover ettiquette because I just don't have the time to remove it every morning.