New spas are tested for leaks at the manufacturers, which will leave water sitting in the plumbing, providing the perfect environment for bacteria and algae growth. Used spas will have the same situation plus the buildup of body oils and grime left by the former owner. Buildup of this biofilm reduces water circulation, jet action, and can provide a breeding-ground for bacteria. The biofilm will help protect bacteria and viruses from sanitizing agents. These microorganisms present a danger because if released into the water, a bather may be contaminated before sanitizers can kill them. Whether it is a new spa or a used one, the first thing that should be done is to fill the spa with water to operational level and then add Spa System Flush. After running the system for at least 1 hour with the Spa System Flush in it, add 1 gallon of liquid chlorine to the spa and circulate for 6 to 8 hours or overnight. Go ahead and drain your spa and refill with fresh water, get the water in balance and add your sanitizing chemicals. Call or stop in at Swim Rite Pools for further information.