Let's tell the truth about salt/chlorine generation...

Now you can practically manufacture your own chlorine in your own pool. Sounds great doesn't it? Phenomenal money saver, right? Well,...

Let's look at this in a holistic or complete way, especially in light of the tremendous press that salt or saline-chlorine generation has been getting. 

The thought is, take common salt in the form of Sodium Chloride (NaCl) & break it into its elemental components. In layman's terms we have water (H2O) + salt (NaCl) passing through an electrolytic cell (sometimes called a turbo cell or ECG - electronic or electrolytic chlorine generator) which has specially coated plates and an electrical current running in them. The positively or negatively charged current breaks the molecular bonds into Hypo-chlorous acid (HCl) and sodium and oxygen (specifically NaOH). Hypochlorous acid is what we're looking for and need as our primary sanitizer. Sounds pretty simple and chemically speaking, it is. (by the way, that's a picture of a chlorine molecule)

As you can figure out, there's a "BUT" coming!

The "but" is that there's a bit more to this chemistry. That ECG is also "creating" other compounds as the water, with various dissolved minerals such as calcium, phosphorous, sulfur, passes by. Salt-chlorine generation causes 3 main issues that the pool owner needs to be aware of:

1. Difficult to manage pH levels, especially high pH.

2. Scaling of pool surfaces & equipment.

3. Stray electricity adding to the electrolysis corrosion & metal staining problem.

High pH is always a problem with saline pools. The method of generation continually pushes or forces the pH up. If you live in an area where the pH of the source or tap water is low or lower, such as in various parts of the Northeast US, that "problem" can actually help your overall water balance. As long as you are regularly monitoring the pH & making adjustments as necessary, you should be in good shape.

Other parts of the country are not so lucky. Areas of "hard water" such as in Arizona or Florida will constantly battle high pH. There are cities & towns where the pH out of the tap is in excess of 8.0. Acid will need to be added on an ongoing basis to maintain a "stable" pH level of 7.4 - 7.6. These areas also typically have higher contents of dissolved heavy metals such as iron, copper or manganese which can lead to staining.

The other high pH pool issue is associated with virtually any concrete, tile or aggregate finished pool. When new, these finishes will continually force the pH level high. And when the plaster finish is brand new, it's not unusual to see pH levels in excess of 10.0 or higher.  In fact, newly plastered pools should NEVER add salt to the pool until 30 days after being filled to allow the curing process to begin. Neglecting this delay will cause abnormal staining or mottling of the pool's finish & surface (which MAY not be able to be treated).