Alkalinity Increaser (Sodium Bicarbonate). Low total alkalinity may result in corrosion and pH bounce. Alkalinity Increaser raises Total Alkalinity and buffers the water against changes in pH. Total alkalinity should be maintained between 100 ppm and 150 ppm. Minor affect on pH. 1.5 pounds of Alkalinity Increaser per 10,000 gallons of water will raise alkalinity 10 ppm.