Silver is used as a bactericide while copper is often utilized as an algaecide. As water comes into contact with these minerals, positively charged ions are released; these ions destroy negatively charged ions (contaminants). These particular minerals are therefore well-suited for use as sanitizers in water environments.
Silver and copper are more effective in their ionic forms, meaning the molecules are independent and carry a positive charge. These ions are attracted to negatively charged organics (contaminants) such as bacteria and algae. Once attached, these ionic elements destroy the contaminants by penetrating their cell walls.
Because ions are not affected by sunlight or heat, they can remain active in water for extended periods. They are only removed by reacting with contaminants or water replacements. There must be a constant flow of these charged ions continually introduced to the water in order for this process to be effective.
There are many types of devices manufactured that can accomplish this process using active or passive methods.
“Active” devices create ionic silver and copper by applying a low-level direct current to electrodes which are plumbed into the filtration system. The electrodes, which are made from of silver, copper and zinc combinations, quickly release their ions into the water as they erode from electrolysis. The electrodes must be replaced periodically, and the water must be tested regularly to ensure the silver and copper levels do not rise to a point where staining occurs.
Sequestering agents are recommended with this method to prevent any possibility of staining. These devices were common in the 1980s and ‘90s, but they never reached mainstream status as sanitizers. Most pool professionals feel they were oversold as a total replacement to chlorine, or were installed and used improperly. Recent technology seems to take into account the lessons learned from the past, but ionizers are not what most people think of when mineral sanitizers are discussed.
Passive-method devices are usually what come to mind when discussing mineral sanitizers. They do not use any electricity, instead utilizing a flow-through cartridge containing a substrate that is coated with silver or impregnated with a combination of silver and copper. The substrate is made of small pebble-sized pieces that are retained in a plastic cartridge. The cartridge is then installed in a vessel that is plumbed into the spa’s filtration system. As the water passes around the substrate, silver and copper ions are slowly released.
Sequestering agents are not necessary, since the ions are released so slowly. The cartridge contents will remain active for up to 4 months in portable spas. This method was introduced by King Technologys and is termed the “frog” mineral system. Passive devices are a perfect complement to salt-water chlorinators. They do not interfere with chlorine generation, and users can turn the chlorine production rate down, making the electrolytic cell last longer. Passive devices are a preferred method of using copper and silver vs. adding them via a powder or liquid form, because those products are usually mixed with chemicals.
The EPA plays an important role in the regulation of mineral sanitizers. While the copper and silver elements are considered safe, when an efficacy claim is made regarding algae or bacteria control, the EPA regulates its use. Therefore, make sure the product you use has an EPA registration number, lists the active ingredients, and shows all the cautions that the EPA requires. Though the EPA regulates and verifies the claims of mineral sanitizers, they do not regulate the product’s potential to stain or cause other problems. Look for products that are guaranteed to work and guaranteed not to stain the pool.
Benefits of mineral sanitizers
Neither the active nor passive methods eliminate the need for chlorine in a swimming pool, because minerals lack the ability to oxidize dead contaminants. Fortunately, the two biggest benefits of using minerals are a reduction in the amount of chlorine needed to maintain a residual, and the ability to maintain a lower chlorine residual. With a mineral sanitizer, you will notice at least some of the following:
• Reduction or even an elimination of algae
• Fewer skin and eye irritations
• Reduction in shock treatments required
• More stable pH levels
• Total Dissolved Solids do not increase as quickly
Keep your Spa and pools sparkling clear with less work through the use of mineral systems!
