Most likely a “salt water hot tub” is not what you think.
“Salt water tubs” are not a new thing. They were popular in the eighties and early nineties and fell out of favor due to a number of factors including cost and the corrosive nature of salt. Recently, however, “salt water” spas have become a highly-advertised option creating a resurgence in their popularity. However, with all the hype, most likely a “salt water hot tub” is not what you think.
Many people imagine that a “salt water hot tub” is filled with the equivalent of clean ocean water. Others believe it is something like bath water with epsom salts. And most people mistakenly think that salt water hot tubs do not use chlorine. Saltwater hot tubs and pools are not actually chlorine-free; they simply utilize added salt and a chlorine generator to make the chlorine right in your tub, instead of you directly adding chlorine to the water.
A chlorine generator (also known as salt cell, salt generator, salt chlorinator, salt system, or SWG) uses electrolysis and dissolved salt to produce a form of chlorine – essentially the same chlorine sanitizing agent that has commonly been used in pools and hot tubs for decades.
Yes, it is true that this “salt water” method reduces the chlorine and bromine in the hot tub. But there is newer tech available that does an even better job with even fewer toxic chemicals.
The GOOD thing about Chlorine
Chlorination is the most widely used method for disinfecting water supplies in the United States. According to the National Institute of Health, “chlorination is the standard of disinfection against which others are compared.” The near universal adoption of this method can be attributed to its high performance as a disinfectant, which has been established by decades of use. It has been so successful that we no longer worry about epidemics of waterborne diseases. Water safety is now virtually taken for granted. Simply put, chlorine is used to disinfect water because it works.
The BAD thing about Chlorine
Chlorine is a very powerful chemical and is considered toxic. How toxic at very low levels is a matter of debate. There certainly is evidence that very low levels are safe, afterall, it is in our drinking water! On the other hand, you can find some very scary articles about chlorine on the internet. Chlorine works, but it is toxic and it is wise to limit our exposure with the low chlorine options we have available.
The UGLY situation about Chlorine Products
Just like we often see on food labels, many different names are used to disguise the ingredients used. With water care product labels, we see many names that disguise the fact that it is actually chlorine. We recommend that you do your research and know exactly what chemicals you are using. Use water care products cautiously and only as directed. And now you know that “salt water hot tubs” are not chlorine free. They actually make chlorine right in your tub.
Why does the water in a hot tub need to be disinfected?
Let us be very clear that well-maintained spas are easy to keep clean and healthy. When neglected though, biofilms containing mold, algae, bacteria and other microbes can become a problem. Biofilm formation begins when free-floating microorganisms such as bacteria come in contact with a surface and begin to put down roots, so to speak. One example of a biofilm that we are all familiar with is tooth plaque. Severely contaminated spa water could be the result of excessive bacteria in biofilm, which may resist normal sanitizing methods. Food, drink, leaves from trees and other natural organic matter, small amounts of contaminants in water and especially us humans introduce microbes to the water in a hot tub.
New Water Treatment Tech: An ounce of prevention is worth a pound of cure
In recent years there have been some important new technologies come on to the market that approach the problem of clean spa water differently. These new systems use minerals, enzymes, ozone and UV light. Again using the analogy of tooth plaque (biofilm), it is easier and more effective to keep plaque from forming in the first place than to rely solely on having the hygienist scrape it off. In other words, these new technologies work to prevent microorganisms from forming biofilms in the filters, pipes and tub, requiring much less chlorine to disinfect what is free floating.
Let’s look at the numbers:
Chlorine and bromine systems: 3-5 ppm chemicals
Salt water tubs: 1-3 ppm chemicals
Enzyme and Mineral systems: app. 0.5 ppm chemicals
EPA standards for drinking water: up to 0.4 ppm chemicals