One of the most popular attractions in a public or private aquatic facility or health club is the spa, hot tub or whirlpool bath which features hot, swirling, water that provides a sense of relaxation, health and well being.

But this popular attraction has become a major health concern for most facilities because of increased risk of bacterial infection resulting in the common Pseudomonas Aeruginosa, which creates an uncomfortable skin rash or the more serious Legionella Pneumophila (Legionnaire's disease) which has been evident on a cruise ship and in some display and backyard spas.

Dr. R. Neil Lowry, a Ph.D in inorganic chemistry, is a consultant to the swimming pool and spa industry and a regular contributor to this publication. He has written several articles on hot water maintenance and stresses the importance of using the proper sanitizers for the unique conditions of spa water, maintaining adequate levels of sanitizers and chemical parameters for spa water, and most importantly, the regular dumping of spa water to insure cleanliness.

This article is a synopsis of several articles produced by Dr. Lowry and should be an easy guideline to the proper maintenance of any hot water installation.

Second, bromine residuals are more effective than chlorine over the broad range of pH values experienced in the small volumes of spa water. Being slow dissolving, bromine tablets lend themselves to a constant feed system. The one negative aspect of brominating tablets is that they are an acid feed sanitizer with a pH of 4.8 which can quickly deplete total alkalinity and lower pH.