Coupon code applied successfully : Free shipping on orders over $50 “Shock” has been added to your cart. View cart → PH Minus$4.00 Lowering your pH will also lower your alkalinity. The ideal pH level is between 7.5 and 7.8 ppm. PH Minus quantity Add to cart Category: Pool Chemicals Related products Add to cart Alkalinity Increaser $10.50 Add to cart Salt 40lb $14.50 Add to cart Stabilizer $8.50 Add to cart Calcium $8.75