AquaDoc Hot Tub pH Decreaser - 64oz - Spa pH Down for Water Balance - Hot Tub Chemicals Made in USABrand: MAV AquaDoc Features: Why Decrease Hot Tub pH? Did you know that the water in your spa should be maintained at a pH of 7. 2 to 7. 8 and total alkalinity from 80 to 140 ppm? Using a pH down for hot tub or spa pH decreaser will help you maintain your hot tub chemistry. pH Down For Hot Tub Spas AquaDoc's spa pH reducer helps you maintain the balance of your hot tub's chemistry. If your spa's pH measure is outside its range, it is important to use