Hot Tub Chemical

Hot tub chemicals are a pain! Our customers have been using the Aero-Spa™ system as the primary water treatment process for years without harsh chemicals. Because we cannot control how your hot tub is used/maintained and according to the EPA we must recommend maintaining at 1 – 2 PPM of an approved residual sanitizer to minimize cross contamination of users. To put this into perspective, the EPA recommends 4 PPM residual chlorine in public drinking water, so the concentration of chlorine will be 4x less than the water you drink or bathe in. To obtain a 1 PPM ratio in a 500 gallon hot tub, you would need to add about 0.63 OZ (1.25 tablespoons) of regular household bleach (6% sodium hypochlorite). If you substitute swimming pool chlorine (10% – 15% sodium hypochlorite) you would need about half as much.

The suggested method on fill and start-up would be to use sodium dichlor on the initial application of the sanitizer and then the first time you need to adjust the free chlorine. Any subsequent time the free chlorine needs to be adjusted use 0.63 OZ (1.25 tablespoons) of regular household bleach (6% sodium hypochlorite). The reason for this is that the sodium dichlor contains cyanuric acid (CYA) as a stabilizing agent. The CYA keeps the chlorine from degrading from sunlight and heat. If you continue to use soduim dichlor to raise the free chlorine, over time the CYA builds up in the water and makes the chlorine ineffective. The initial application of sodium dichlor will have enough CYA to stabilize the chlorine for the long run. This method will minimize maintenance and save you money! The easy formula is first and second application is sodium dichlor and all others bleach.

In a hot tub without ozone, much of the chlorine reacts with compounds such as body oil, perspiration, etc to form chloramines. Chloramines have no sanitizing ability and produce the harsh “chlorine” smell. Because of the superior oxidizing ability of ozone, these compounds are quickly reduced and filtered out. The keeps the chlorine free to work as a sanitizer if needed in adverse conditions.

If you have a hot tub, you are very familiar with the issues related to the use of chemicals to sanitize your hot tub. The chemicals such as chlorine, bromine, pH up, pH down, shock (hydrochloric acid), clarifier and de-foamers are all used to sanitize and clarify the water. This concoction of hazardous materials produces vapors and substances that cause respiratory irritation, skin rashes, discoloration of clothing and environmental issues.

These chemicals need to be added continuously to be effective. After a short period of time the water becomes saturated and the chemicals are no longer effective or the chemistry becomes so unstable that it is impossible to balance to the required levels.

When the water becomes chemically saturated the water must be changed. All of the chemical laden water is typically discharged to the environment with complete disregard for its effect. In addition to the environmental issues, the hot tub must be refilled. Depending on the water source used for refill, the balancing act must begin again to adjust for hardness and iron content. Additionally, a significant amount of energy is consumed in pumping the water and heating the water from somewhere around 50º to 100º + degrees.