Beginner
Use 3 g (1/2 level teaspoon) per 150 L (40 US gallons) twice a week. Dissolve in at least 250 mL (1 cup) of freshwater. Check alkalinity every 2 weeks and adjust amount or frequency accordingly. For precise dosing, use the Seachem Digital Spoon Scale.
Advanced
Check alkalinity (use MultiTest™ Marine pH & Alkalinity to test alkalinity levels), then follow addition regimen above until alkalinity is adjusted to 3-6 meq/L (8-17 dKH). Each 3 g/150 L will raise alkalinity by about 0.25 meq/L. Quantity or frequency can be adjusted, but do not exceed 12 g/150 L per day. Thereafter, use as required to maintain alkalinity.
Expert
After determining the alkalinity consumption rate, set up a continuous drip system. Use the following formula (or skip the math and use our Dosage Calculator) to determine how much to add to your top–off water: m=0.08va (m=grams to add to top off water, v=volume of tank in liters, a=amount to raise alkalinity in meq/L). For example, if you want to raise your alkalinity by 1 meq/L in a 200 liter tank, then you would add 0.08x200x1=16 g into the top–off water. [For reference: 1 gallon=3.8 liters, 6 g=1 teaspoon].
DO NOT OVERDOSE: Excess alkalinity may enhance the loss of calcium, magnesium, and strontium. Do not directly mix with any calcium, magnesium, or strontium supplement. Best if calcium & carbonate additives are added on alternate days or at least 30 minutes apart.