I had trouble at the end of last year with keeping my Free Chlorine level up. On Monday my FC was almost nothing and my TC was 2. I put in all the bleach I had in my house on Monday evening. Since then, my FC has been around 4.7 and my TC has been 4.5. During this time I've had my chlorinator running about 3 hrs per day at 100%. My pool water is covered with a solar cover and the pool temp is about 78 degrees. Would the chlorine have gone down if my chlorinator hadn't been working? How long does it take for the chlorine to dissipate if no new chlorine is going in?? I want to make sure my chlorinator is working.