The pros for using salt water chlorine generators are clear.
- The convenience of not handling chlorine on a weekly basis.
- Salt generators also have a softening effect on the water giving it a silky feel.
However, we believe the cons far outweigh the pros in several areas. One major drawback is salt generators produce scale on an ongoing basis. Another major problem is high pH. As the salt is converted to chlorine, the generator plates produce a strong alkaline substance which results in an ongoing high pH level. After adjusting, the pH typically creeps up again within 2-3 days.
The Problems Get Worse
A major problem with scale formation is it reduces chlorine production which can result in cloudy water and algae growth. The scale formation can also result in cell failure which can be very expensive to replace. White flakes from pool returns indicate the formation of scale on the plates.
Staining is another major problem with salt chlorinators. This shows up as streaks down the pool sidewalls. Cloudy water is also common & is usually the result of pool quality salt.
The biggest problem, however, is complete generator failure. This can sometimes be caused by calcified or dirty electrodes. But the number one factor is phosphates in the pool water.
Phosphates are common in tap water and can be caused by grass, leaves and even rain. It is very difficult to be phosphate free, as phosphates are the nutrients for algae. The high algae count causes increased chlorine demand which sometimes interferes with the mechanics of the chlorinator.
An ongoing issue is always corrosion to metals in and around the pool. Many manufacturers will not warranty their products if a salt generator is on the pool.
If You Must, Choose Your Salt Wisely
If you do go down the salt water chlorinator route, it is most important that you use good quality salt. Don’t just buy the cheapest salt available. Low quality salt can cause staining, scale and increased demand for chlorine. The salt with the most impurities are usually produced via mining (rock) or solar evaporation.
Mechanically evaporated salt is usually the best as it has the fewest impurities. The high heat used in producing this salt destroys the natural contaminants, a process not possible in solar and mined salt.
How do you tell if you purchased poor quality salt? The shape of the crystals could be a giveaway. Irregular crystals usually contain the contaminants that cause the problems. The more irregular the crystals, the more impurities they contain. The more uniform the crystal, the purer it is, making it the best choice for pools. The best quality salts contain anti-scale, anti-stain reagents and are guaranteed to work best in saltwater pools.