How often should I shock my Spa? Ciara June 18, 2018 01:37 Updated Follow You need to use an approved oxidizer (spa shock) at least once a week or after heavy usage of your spa, spa shock oxidizes the organic matter that makes the water cloudy.Important: If you are using a chlorine free sanitizing system you will need to shock the water with a Chlorine Free Shock (Poppits Quick Fix) go through guidelines on the brand. Related articles What is the difference between Poppits Chlorine Free Sanitizer and Spa Protectors Chlorine Free Sanitizer? What is Spa Shock? Do I need to use spa shock in conjunction with Bio Armour sanitiser? Comments 0 comments Article is closed for comments.