HOW MUCH pH UP/DOWN IS NEEDED PER GALLON?
Start out with one milliliter per gallon. Wait 15 To 30 minutes, and test your water again. Frequently you will only need 1 to 2 ml of pH Up/Down per gallon of water. You may need additional pH Up/Down if you have hard water. The General Hydroponics Flora Series is pH buffered to facilitate keeping the pH in a favorable range.