Add 5 g (1 level teaspoon) for each 80 L (20 US gallons). Dissolve in at least one cup of freshwater. This dose will also raise alkalinity by about 1 meq/L. Add daily until pH stabilizes at 8.3. This will take from a day to a week, depending on original pH and alkalinity. Thereafter, use biweekly or monthly to maintain a pH of 8.3.