by Myles McMorrow, May 20, 2009
Swimming pools have come a long way over the years when it comes to sanitation. Back in Roman times, pools were heated, but they had to have the water changed a lot to keep them clean and clear. This was common practice until chlorine came along about 100 years ago, to kill bacteria and algae keeping them sanitized for use. Over the years people are leaning away from chlorine trying to have a more environmentally friendly pool. Technology has made leaps when it comes to all the options of pool sanitation on the market today.
One such method employed these days is the use of UV light . UV light rays with wavelengths of at least 254 nanometers kill microorganisms such as crypto by altering their DNA structure, hampering their ability to grow cells and form biofilms. UV sanitizing systems use a chamber plumbed into your piping and high amounts of UV light radiation is projected into the pool water as it passes through the chamber. This method is highly effective at killing bacteria as well as most RWIs Recreational Water Illnesses. This was the method used in China during the last Olympics in the Water Cube to maintain a clean clear healthy pool.
Have you ever smelled the fresh air after a thunder storm? The fresh air smell is a byproduct of lightning called ozone. Ozone is a powerful sanitizer that cleans as well as disinfects. Ozone is so powerful that it has 3 atoms of oxygen in it and is created by UV light or from Corona discharge (high voltage spark or lightning). Ozone gas (the O3 molecule) is added to the pool through a venturi system. As water passes through a fitting it sucks in the air from a chamber that is rich in ozone and mixes it with the water making it fairly effective at purifying water. The first time this was used for purifying commercial drinking water was in France in 1906.
Minerals can be used for sanitation too. A very popular system is the Nature 2 system using Copper and Silver. Silver has natural antibacterial properties that are used to sanitize the water and the Copper Is a natural algae inhibitor. Although this system helps to keep your pool clear, you still have to use chlorine, but at a much lower level. A typical Nature 2 cartridge is about $100 and will last 6 months.
Catalysis is the process brought forth with the use of Enzymes, when the substrate is changed. It could be broken down or combined with another molecule to make something new. When the enzyme lets go, it returns to normal, ready to do another reaction. The substrate is no longer the same. The substrate is now called the product. This is very helpful at breaking down all the bad stuff people take into a pool such as Suntan lotions, sunscreens, body oils, sweat, hair products, vegetation (algae), and airborne vehicle exhaust as well as many more. This is a great product to use when opening a pool or closing it for the winter. Our final alternative santizer is the use of Copper Ions to sanitize the water. A safe, low voltage DC current is applied to 2 copper electrodes, plumbed inline on the equipment pad. As the ions attempt to move from one electrode to the other, they are swept away by the water rushing between the two electrodes. Ions have the ability to pierce the protective outer membrane of a cell and disrupt enzyme balance thereby killing algae. Although lethal to bacteria and algae, pool ionizers are completely safe for humans. When used improperly however, electric ionizers have the ability to stain pool plaster.
Another environmentally friendly way to sanitize your pool is by converting to a salt system. Salt Water Generators make your own chlorine. By adding salt to the water, and applying electrolysis, the H2O + NaOCl2 is converted to H2O + Cl2 + NaO (or something like that!). Why is this environmentally friendly? Because it reduces the manufacture and transport of chlorine tablets and chlorine shock. But it does still use chlorine - and it is very hard not to use chlorine in a pool.
For those that try to go Chlorine Free, the cost can add up, with extra filtering and extra alternative chemicals. Unless you go completely Natural, with a naturally filtered pool. But you have to give up on the idea of a blue pool, instead opting for green. I like Green! Green is a good color.
