Timing is Everything -- If You Want an Easy Swimming Pool!
Adding chlorine to your swimming pool in the evening, instead of the morning can reduce cut your chemical costs in half.
Why? At night, chlorine is used up doing useful work in your pool, like oxidizing all that sweat and sun-tan lotion from your pool party. During the day, it mostly is wasted -- lost to UV in the sunlight.
Depending on stabilizer levels, and sunshine, you can lose half of the chlorine in the pool in as little as 30 minutes! Even when your swimming pool is stabilized, you can lose half the sanitizer in your pool in 4 hours. But, at night, all of the chlorine used up, was used up doing something useful to your pool water!