Dear Jim: The chemicals to treat my swimming pool water irritate us and are expensive. I thought a no-chemical electric ionization purifier might be better. Do they work well and will my electric bills be higher? – Ron A.

Dear Ron: There are several electrical methods used to purify swimming pool and spa water and ionization is an effective one. These kits use little electricity, so you probably won’t notice a change in your utility bills. Some models are solar-powered, so they operate for free with no wiring or plumbing to hook up.

It is still a good idea to use some purification chemicals with most ionization systems, but the amount needed is only a fraction of the normal chemical-only concentrations. The amount of chemicals used is low enough to avoid common skin and eye irritation, dryness, bleaching of suits, etc.

NASA has done much research over the years on using a combination of metal ions in the water to purify water on spacecraft. As far back as the Roman Empire, water was stored in silver containers and silver cups were used because just a very low level of silver ions killed many microorganisms.

Most pool and spa ionization purifiers use copper-silver electrodes with traces of other metals. Silver ions kill microbes and copper ions stop algae growth. You still must control the acidity of the water with standard pH-balancing chemicals. Some use special natural materials for balancing.

The ionization control unit plugs into a standard electrical wall outlet, but the voltage going to the ionization electrode in the water is low and safe. The ionizer chamber, which holds the electrode, is located in the filter plumbing outside the pool. All of the wiring, hardware and plumbing connections are included in the kit. You can install a system yourself.

The solar-powered ionization unit is only about 1 foot in diameter and it floats on top of the water. A copper-silver electrode underneath it is submerged in the water. The sun shines on the small solar panel built into the top of the unit. This creates a very low electrical current through the electrode to create the ions for purification.

After you install the ionization unit, turn on the control unit. As it runs, the ion level in the water begins to increase. Still use chemicals during this startup period. All of the systems include a copper ion test kit. When the copper ions reach the proper level, set the output dial lower. Gradually fine tune it to maintain the proper ion level.

Another similar system uses a different type of electrode to create oxygen, not ozone. The higher concentration of oxygen in the water oxidizes impurities.

You can switch the copper electrode on only as needed to control algae.

Write for (instantly download – www.dulley.com) Update Bulletin No. 893 – buyer’s guide of 12 electric/solar ionization purifier manufacturers listing pool/spa capacities, features, controls, diagrams, prices, and tips to keep pool water clear. Include $3 and a business-size SASE, and send to James Dulley, 6906 Royalgreen Drive, Cincinnati, OH 45244.