The following list represents the basic selection of chemicals available for effective spa maintenance. Often referred to as dichlor, this low-cost 100 percent soluble chlorine sanitizer produces no residual effect on acrylic or fiberglass shells.
Some sequestrian agents can remove stains from fiberglass shells in conjunction with brushing.
Clarifying chemicals cause these particles to coagulate or combine into solids large enough for spa filters and vacuums to remove. Clarifying treatments are prescribed for spas that have not received proper care in the normal course of operation. Scaling chemicals dissolves calcium and rust spots that may attach to the shell. The acidic properties of these chemicals may reduce pH levels. This helps prevent metal releases and scale formations on the walls of the spa.