spa pool sanitiser

Which is best, UV or Ozone spa sanitisers?

UV Spa Santising systemsWe are often asked: "Which is best, UV or Ozone systems and do they work?"

There is a lot of discussion in the spa industry around which is the best automatic sanitising system for spas and swim spas. The truth is, the ultimate solution is to have both! Read on to find out why:


Ozone loves to share! The science of ozone spa sanitisers: 

The normal Oxygen we breathe is called O2, and is made up of only two chemically linked Oxygen atoms. Ozone, called O3, is Mother Nature’s purifier and disinfectant. The 3, stands for the three oxygen atoms that compose ozone. Ozone loves to share. Within ozone, one of these Oxygen atoms has a weak hold on the others and is more than willing to transfer electrons with other organic substances. This single Oxygen atom binds with the other substances, causing it to oxidize or turn into something else. Rust is an example of what happens when steel oxidises. When the weak Oxygen molecule in Ozone attaches to other organic molecules in the water, it oxidizes them. In effect, the Ozone “eats ‘em up” and voila! Clean, fresh, purified water.

Ozone, The spa water clarifier:

By oxidising metals and other organic compounds, ozone can cause them to drop out of suspension, allowing them to be filtered out of the spa's water by the Purezone filtration system. Without the use of the ozone clarifier, superfine particles can cause the spa's water to remain cloudy, cause foaming and bad odours resulting in the need for more chemical water treatment methods.

What are UV sterilisers and do they work? 

UV sanitising systems are a natural, chemical free and chlorine free way to sterilise spas. The UV technology found in spa pools is not new. Although the science behind UV spa sanitisers sounds like it is out of your favourite futuristic science fiction movie, in fact, you will find it has been purifying drinking water and public swimming pools around the world for nearly 60 years. UV sterilization kills 99.9% of waterborne viruses and bacteria, including the real tough bad guys like Giardia and Cryptosporidium  viruses. For this reason, it is now mandatory on public swimming pools in many states in the US.

The science behind UV spa sanitising systems: Microbe Death Ray found!

Ultraviolet(UV) spa sanitisers deploy a non-chemical process that uses germicidal UV light rays to sanitise water in spas. Think Death Ray for microbes. Maybe it is an accident of evolution or justOzone Spa Sanitising systems bad luck for microbes but the energy of some chemical bonds in DNA and RNA matches that of the UV radiation. The energy from the radiation is just right to break some of the chemical bonds. The result is that the microorganisms, such as algae, bacteria, viruses, cysts and protozoa, cannot reproduce and are killed. What is sad news for microorganisms like those pictured to the right, is great news for spa owners everywhere. Additionally, the highly concentrated electromagnetic energy also destroys organic matter, eliminating the formation of dangerous chlorine by-products. 


“There is a lot of data, precedent and science behind UV. The most exciting thing is its ability to make Cryptosporidium inactive. UV can stop crypto almost immediately. In fact, UV has the same effect on Giardia, a protozoan parasite responsible for another recreational water illness called giardiasis.”


Tom Lachocki, PhD, CEO of the US National Swimming Pool Foundation.

What do Ozone and UV sanitisers cost?

The price of Ozone and UV sanitiser systems varies greatly depending on the size of your spa and the manufacturer but it is safe to say that UV and Ozone systems are well worth the price of upgrading. They save you time and money by reducing chemical use in spas and swim spas.

So if you want clear water, free from viruses and bacteria, with very little or no chlorine use, select a spa that has both ozone and UV systems installed. 


Learn more about Ozone and UV sanitisers for spas and Chlorine free sanitisers for spas.


What do you think about UV and Ozone spa sanitising systems?