JudiWV

Yes, just repeat the test. Perhaps you are "on the edge" and almost there. Shoot for a shock level of chlorine that is an FC that is 40% of the Cyanuric Acid (CYA) level unless the CYA is very high in which case you should consider diluting the water to lower the CYA. The CYA should probably be around 50 ppm or so and not more than 80 ppm at the most. Read the Pool School for more info. Since the water level is down a bit, can I add water to dilute the CYA? Also, if I put 7 gallons of clorox yester day, how many should I add this time? The CYA is in the 80-100 range. I can probably add 1 1/2 inches of water to the pool which holds 13,500 gallons.

I'm having problems with FC also. Did bucket test and added 7 gallons clorox and got desired results. Next morning...0-FC again. All other readings are good. Pool is 13,500 gal. Do I need to do this again with even more clorox? Pool store owner said "I wouldn't worry about it". Really, after i spent $200.00 there already this season?