Water Chemistry Problems - Shock

PROBLEM:  Not responding to shock treatment 

POSSIBLE CAUSES:  Failure to add enough shock to effectively deal with the problem.

SOLUTION:  Shock the water per product label directions and test the Free Chlorine level after a few hours. Keep the filter running continuously until the water is clear. If the Free Chlorine level is below 3 ppm, add a repeat dose of shock. Continue testing and add additional shock until a Free Chlorine level of 3 ppm is maintained for an overnight period. Resume normal chlorination and filtration.