Chemical Attraction

By Elissa Sard Pollack

 

In a world where almost anything can be purchased online, cell phones can receive flight delay alerts, and machines of all kinds run on timers or sensors, it is no surprise that pool and spa water care is evolving. Fortunately, it’s getting easier, too. Automated systems, including saltwater chlorine generators, copper/silver ionizers, mineral purifiers, ozone generators, erosion feeders, ultraviolet sanitation systems, and combinations of the above, have replaced the tedious and sometimes complicated water care methods pool and spa owners dealt with in the past.

Saltwater Chlorinators

One needs only to look at the growing plethora of products (algicides, shocks, pH and alkalinity controls, and so on) being marketed for use in saltwater pools to understand that electrolytic saltwater chlorination continues to gain popularity. Saltwater chlorinators typically contain a catalytic cell that converts sodium chloride to chlorine, so operators never have to add traditional forms of chlorine to the pool. This eliminates the need to transport and store chlorine in bottles or buckets, reducing waste and saving time. Some models even come with on-board diagnostic systems that track water temperature, sanitizer levels, and other factors that can help identify the cause of any problems that arise, removing much of the guesswork in water treatment. Units with or without this intelligent diagnostic feature typically come in two or three sizes for small or large pools and range in price from about $500 to about $1,000.

Copper/Silver Ionizers

Copper/silver ionizers also use an electrolytic process to treat pool water. These units introduce algae-killing copper and/or silver ions into pool or spa water, which dramatically reduces, but does not eliminate, the amount of sanitizer and other preventative care products required. It’s a good option for those who want to reduce the amount of chemicals needed to maintain water safety and clarity. These units cost about $400 to $2,000, depending on size.  

Mineral Purifiers

Mineral purifiers also reduce the amount of sanitizer needed to treat pool and spa water and represent a simple, inexpensive solution. The most basic mineral purifiers are essentially cartridges that fit inside spa filters. Larger units work in a similar fashion, fitting inside pool filter cartridges. Most purify water as it passes through the unit by releasing a proprietary blend of silver and other ingredients that work together to attack other contaminants. These units range in price from about $25 for spa-size units to a few hundred dollars for pool-size versions.

Ozone Generators

Ozone is a powerful oxidizer, but its effects are somewhat short-lived. Ozone generators use either UV or corona discharge (CD) technology. Nearly all new hot tubs today are equipped with an ozone unit (typically CD-type), but

adding a UV ozonator to your hot tub is simple—it’s essentially a box with a special lamp inside. The lamp emits a specific wavelength of UV light that converts oxygen (O2) into ozone (O3). The ozone then purifies the water. Whether generated by UV or CD, ozone can dramatically reduce the need for other chemicals, although ozone, like the minerals discussed above, requires a small amount of sanitizer. Basic UV ozonators cost about $30 or $40 as add-on items. Though they typically come factory-installed, CD units for hot tubs run about $150; for swimming pools, CD ozone generators start at around $1,000.

Ultraviolet Systems

Another option in automatic sanitation is an ultraviolet system, which uses a UV bulb to destroy bacteria, algae, and other harmful microorganisms in the water. Widely used in Europe and commercial applications, UV systems have made their way over to the U.S. and residential pools. They are gaining popularity because of their ability to eliminate chloramines and greatly reduce the need for traditional chemicals. Though in the upper price range of automatic sanitizers, these systems are highly effective and low maintenance.

Erosion Feeders

To meet the need for a supplementary sanitizer, or even as a primary treatment method, you can rely on some simpler technology that auto­­matically dispenses traditional forms of chlorine or bromine into pool and spa water. Sometimes called erosion feeders, these are specially designed tanks that hold chlorine or bromine in stick or tablet form. Water runs through the tank as it circulates back to the pool and returns with what should be the desired sanitizer level. These basic units are available for $70 to $100.

A more elaborate version of this technology includes an ORP meter, which measures the oxidation reduction potential, or effectiveness of such sanitizers as chlorine, bromine, ozone, and hydrogen peroxide. An even more automated version dispenses liquid chemicals using a peristaltic feed pump. This technology, more commonly used in commercial and industrial applications, is now available for residential use. Fully automated feeders, with meters and feed pumps, have low four-figure price tags.

Putting It All Together

Some systems combine two or more of these technologies to treat water in a number of different ways in hopes of getting the best results. Some combine saltwater chlorination and mineral purification. Others feature a salt chlorine generator that also generates ozone—the chlorine is the primary sanitizer, while the powerful ozone oxidizes unwanted organics. Users can even combine the cleansing forces of ozone with mineral purification. These two are often combined in hot tubs, but the technology is also available for swimming pools.

5 Things to Know Before You Buy

Research. Different types of automation systems work differently. Match options to your pool or hot tub and the level of control you desire.

Keep Working. Most automated water treatment systems automate only some aspects of water care, so you’ll still need to stay on top of your program.

Consider Cost. Prices vary widely. If you want a fully automated system, expect to pay more.

Results Matter. Think of your automated system as an investment in your time and the quality of your water. A good system means greater dosing accuracy, which helps water stay balanced.

Partner Up. Knowledgeable and accessible tech support often matters more than what kind of system is under the proverbial hood.

Photo courtesy of San Diego Pools.