Coupon code applied successfully : Free shipping on orders over $50 View cart “Alkalinity Increaser” has been added to your cart. Carboy Shock$25.00 5 Gallons Carboy Shock quantity Add to cart Category: Pool Chemicals Related products Add to cart Calcium $8.75 Add to cart Alkalinity Increaser $10.50 Add to cart PH Minus $4.00 Add to cart Salt 40lb $14.50