Relax Total Alkalinity Plus - Sodium BicarbonateAlkalinity acts as a buffer, helping to regulate the factors that can throw your pH levels out of whack. Recommended levels are upwards of 150ppm. If alkalinity levels fall below 150ppm, water that has a good free chlorine level can become cloudy. Sodium bicarbonate should be added at the rate of 1. 8kg per 50m3 of water to raise the level by 20ppm.