1 x 7KG Ph- (Minus). 1 x 5KG PH+ (Plus). Use this high quality PH Minus and PH + to adjust the PH value of the water in your spa (7.2 to 7.6 is the optimum for spas). Simply Test Your Spa/Pool water and Follow the instructions on the back of the tubs to Adjust your PH correctly.
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