Do Pool Ionizers work?

Pool ionizers do work. They use a very low level of copper and/ or other metals such as silver to kill bacteria and algae. The recommended copper level is less than half the National Sanitation Foundation 0.3-0.4ppm. for drinking water.

However, getting rid of large quantities of algae usually needs to be dealt with by shocking the pool with an oxidizer such as chlorine. Ionizers can't generate enough ions to clear a pool with lots of algae already in it. This is why it is recommended that the pool be shocked and the pH balanced to 7.2-7.6 before activating the ionizer.

40-50 years ago, swimming pools were plumbed with copper plumbing. The chemicals eventually decayed the plumbing, as did the velocity of the water and the corrosive effects of the chlorine (think what the chemicals are doing to your body, if it was deteriorating your pipes). This put traces of copper into the water. The copper would eventually cause a blue staining of the plaster, because there is an unregulated level of copper being introduced into the water and the chlorine oxidizing the copper causing it to drop out of solution. It also reacted with the blond hair of some bathers, to cause that "green hair" effect - that is oftentimes blamed on the chlorine (remember: yellow + blue = green)! This is usually caused by incorrectly shocking the pool. If you have an ionizer, it is recommended that only liquefied chlorine be used when shocking. Otherwise, it super-oxidizes the copper and it could drop out of solution causing staining.

Not only does copper kill algae, it also kills bacteria and viruses. This leaves you with just organic material which needs to be oxidized to clarify the pool. Usually ionizer owners shock the pool with about 1 quart of liquid chlorine (Clorox) per 10,000 gallons, once a week or if the pool gets cloudy, whichever is sooner. Or you can leave your pool chlorine dispenser set to deliver 0.5ppm at a constant rate. This practice is accepted by many public health localities throughout the United states. The copper (and actually all heavy metals) is an algaecide. It interrupts the plants ability to photosynthesize, thereby killing it. Additionally, more recent studies have shown copper is an excellent germicide and virucide it will be used in hospitals for surgical trays, countertops and even door knobs in the future.

As pools were eventually plumbed with plastic pipe, pool chemical companies started to manufacture liquid algaecides that contained heavy metals (primarily copper, nickle, and silver). Also in the solution, was a sequestering agent, sometimes also called a chelating agent. The purpose of this additive, was to keep the metals in solution in the presence of variations of high & low pH. Without these additives, in the presence of pH extremes, these metals would precipitate out of solution, staining the pool plaster.

So it goes without saying; reasonable pool maintenance must be incorporated in your pool activity, such as checking the pH, alkalinity, and the parts per million of copper in the pool (.03-.04ppm) on a weekly basis. These metals do not evaporate out of the pool, but are consumed by the algae, etc. and could to become concentrated if not checked. Another disadvantage of liquid algaecides, is that these additives eventually wear out, (actually they are consumed by the algae).

Since copper and /or silver are not subject to deterioration from the sun's ultraviolet rays, as is chlorine. The metal that is not consumed by the algae, bacteria and viruses remain in the pool as residual purifying agents. This gives you a very economical and low maintenance method to keep your pool clean.