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Spa Shell
Spa Cover


warm water




filter compartment

Suction side filtration: filters sitting
in un-filtered water always in
contact with the spa water.





Ozone Injection System

Owning a spa with an effective filtration system is important. There are many manufacturers that use a filtration system that does not thoroughly clean all of the spa water. If you purchase a spa with a poor filtration system, you will be soaking and relaxing in a tub that is filled with contaminants. It is important to remember that the more a spa filters, the better it is. Always look for a spa that has an excellent filtering system.

Typically there are two types of filtration systems that you will find; suction side filtration and pressure side filtration.


Suction Side Filtration:

This type of system has a suction at the bottom of the tub and a filter compartment,which holds the filter cartridge, molded into the top side of the tub. Water from the spa is sucked out from two sources. In this particular system, the two sources are the suction and the filter located on the side of the tub. Roughly half of the water is pumped out through the suction and the other half is pumped out through the filter. The water that is pumped out of the spa, travels back into the spa through the jets. Half the water put back into the spa is filtered, and the other half remains contaminated. As the filter becomes dirty, less water is able to travel through it, which forces most of the water to be pumped out through the suction. Your spa is now circulating the same dirty water over and over again, instead of actually cleaning it. Sounds sanitary, doesn't it?

Pressure Side Filtration

Half of the water is being filtered, while the other half remains un-filtered.

As stated earlier, the filter compartment is molded into the top side of this spa. Since the compartment is molded into the spa, the water in the tub will fill the filter compartment. When you take out the filter cartridge, the contaminants on the filter will be put back into the water, since it has to travel through the water on its way out of the tub. This type of filtration system doesn't really fulfill its job at filtering the contaminants out of the water that you will be soaking in.

Ask the company if they are selling spas with suction side filtration. If the answer is yes, it would be wise to move on to another manufacturer. You don't want to put your money into a hot tub that doesn't provide you with one hundred percent clean water. If you do, you will end up spending even more money when you have to buy other products to help filter your spa.

Pressure Side Filtration System:

In this type of spa, there will be a suction at the bottom of the tub, a skimmer at the surface of the tub, and a filter located in a compartment that is separate from the tub. The water will be sucked out through the suction and skimmer, which will travel to a pump. This pump then forces all the water through the filter. The water that is put through the filter is pumped back into the tub through the jets. One hundred percent of the water that passes through the filter is cleaned. All of the water in your spa will be filtered in roughly 3-4 hours.


pressure side filtration

All water that passes through the pump is forced through the filter.

When you take out your filter cartridge for cleaning or replacement, all the contaminants on the filter will be removed from your spa because the filter is located in a separate cavity. None of the contaminants will come in contact with your spa water.

This is by far the best filtration system available on the market. As long as you follow the correct maintenance required for your hot tub, this system will provide you with continuous clean water every time you step into your spa. You can, and will, always enjoy a relaxing and therapeutic experience in your clean water spa.


Another component to consider when shopping for a spa is an Ozone system. Ozone is a form of oxygen in which each molecule contains three atoms (O3) instead of the normal two (O2). However, Ozone is much more reactive than oxygen. It is commonly used to sterilize water for drinking and to remove foul odors from rooms and clothing.

Ozone can effectively oxidize soap, deodorant, hair spray, cologne, makeup, perfume, lotions, saliva and body excrements about 2000 times faster than common chemical sanitizers. It also kills other bacteria, germs, molds and viruses that typically cannot be destroyed by chemical sanitizers. Ozone will even enhance the performance of chemicals used in a spa, such as bromine and chlorine. Since an Ozonator works with the chemicals used to clean a spa, it reduces their usage, which allows you to save money and avoid a spa that strongly smells like chemicals. For these reasons, it is important that your spa has an ozone system installed and working. An Ozonator can ensure sparkling clear, odor-free water that provides a better soaking experience for everyone.

It is important to choose an Ozone system that incorporates an injector. These injectors push ozone into the water and force agitation for optimal destruction of unwanted particles and/or impurities. Make sure you purchase a spa with an injector style ozone system if you are wanting a clean and low maintenance spa.


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