An indoor pool had a combined chlorine reading of 1.5. The pool is 11,730 gallons. I added 1 gallon & 1qt of liquid chlorine(12.5%) to it, to bring the level up to 15ppm. The FC before shock was 1.5ppm.
Well, about 15min after adding the bleach, I tested the water and the FC was only 11ppm(I tested the water in several spots). I added in another gallon of chlorine. Waited about 20min and the FC level was than 16.5, but, when I tested for Combined CHlorine, the reading was 1.0....
How long does it take to eliminate all of the combined chlorine? The ventilation is AWFUL in this pool and there are no windows and air exchange is poor.
I am using the Taylor FAS-DPD test kit. THere is no visible algae in this pool and water temperature is maintained at 90 degrees, as it is a therapy pool.
Thank you for yourhelp,