Two Little Fishies pH-Balance raises both carbonate alkalinity and pH and won’t overshoot the pH too high, making it easy to maintain a pH of 8.3.
Directions: Monitor pH and alkalinity. For each 75 L (20 US gallons) of aquarium water, dissolve 2.5 grams (1/2 teaspoon) in 125 ml (1/2 cup) or more of freshwater. Slowly pour it into the aquarium where there is a strong current for rapid mixing. This solution will raise the alkalinity of 150 L (40 US gallons) of saltwater by about 0.5 meq/L (1.4 dKH) and it will raise the pH by about 0.1 units. Wait 1 hour and check alkalinity before administering a second dose, if it is needed. Use weekly or as needed to maintain an alkalinity between 3 and 4 meq/L, and adjust the pH to daytime range between 8.1 and 8.4.