1. Use a test kit to determine stabilizer concentration in the swimming pool water. 2. If the pool is new, just refilled, or has no stabilizer, add 300g Aqua Stab per 10,000L to give the desired 20 to 30 ppm. 3. If there is less than 20 ppm and Aqua Stab to obtain a level of 20 to 30 ppm. 75g Aqua Stab per 10,000L increases the level 8 ppm. 4. Always maintain the chlorine residual at 1.0 to 3.0 ppm and pH at 7.2 - 7.8. Add Aqua Stab slowly into skimmer or, if desired, pre dissolve in a pail of warm water and then add directly to the skimmer. Be sure filter is clean and recirculate water continuously for 12-24 hours to dissolve completely.