If the pool is clear, then there is no reason to shock it. Elevate the chlorine using liquid chlorine to 4ppm. (Start with 1.5 gallons, check the level after 2 hours of circulation, adjust as needed) Now test alkalinity. Use sodium bicarbonate to bring the level to 100ppm. This can be added through the skimmer with the pump running. You can use a dosage calculator such as https://www.poolcalculator.com to figure out how much of each chemical to add to reach the desired level. Next test the pH. Ideally 7.4 - 7.6 "pH up" or soda ash to raise, and muriatic acid to lower. Then test CYA (stabilizer) adjust to 30-50ppm. Stabilizer must be added through the skimmer. Calcium should be between 200-400 ppm. Calcium Chloride should be diluted with water in a large bucket and then added to the pool. Keep the pump on for a minimum of 8 hours daily, preferably during the hottest time of the day. Please be sure to wait a period of time between each chemical addition. Hope this has helped.