Why Testing your pH & Alkalinity is Important

Many people take a see no evil hear no evil approach to water care: if their hot tub water is clear then there is no need to test and balance the pH and alkalinity. This attitude can cost spa owners thousands of dollars each year in repairs.

The fact is that water can be crystal clear and odorless, and imbalanced water chemistry can still be wreaking havoc on your hot tub equipment. Let’s take a look at what imbalanced water chemistry can do to your spa, and how to prevent the damage it causes.

Low pH

Low pH causes acidic water, leading to corrosion of the plumbing and spa equipment.

A common cause of low pH is oxidizing shock acting as a natural pH Decreaser, gradually lowering the pH level with each use. OxySpa Chlorine Free Oxidizing Shock has overcome this pH lowering effect with special additives to eliminate the drift.

Oxidizing shock is used to break up dead organic matter (killed by your sanitizer) and prevent cloudy water. Without this shock, the dead organic matter will remain in the water causing it to become cloudy and serve as a buffet for new bacteria.

Test your spa water weekly and balance your pH and Alkalinity as necessary per your test strip readings.

Ideal pH range is between 7.2 and 7.6.

High pH and/or High TA

pH above 7.6 and Alkalinity above 120 ppm results in scale formation on the hot tub equipment. Scale buildup is the leading cause of premature heater element failure.

Problem	Remedy
pH High, TA Normal	Add Alkalinity & pH Down to lower pH. If TA drops below normal range, add Alkalinity & pH Up to bring it back up.
pH High, TA Low	Add Alkalinity & pH Down to lower pH, then add Alkalinity & pH Up to bring TA back into range. It won’t raise pH above normal range.
pH & TA High	Add Alkalinity & pH Down to lower high TA and pH.
pH & TA Stubbornly High	Add Acid Magic to lower very high TA or pH.

Low Alkalinity

Low alkalinity causes your pH balance to drift from one extreme to the other. This is why adjusting your Alkalinity first (during spa start-up) makes balancing your water so much easier.

The ideal range for alkalinity is between 80-120ppm.

Problem	Remedy
pH High, TA Low	Add Alkalinity & pH Down to lower pH, then add Alkalinity & pH Up to bring TA back into range. It won’t raise pH above normal range.
pH Drifts Wildly	Commonly caused by low TA. Bring TA into line with Alkalinity & pH Up as needed and make final adjustments to pH, if necessary (usually not necessary). Help lock pH into range with Control the pH.

Here are some tips to make water balancing trouble free:

Tips

• IMPORTANT: After adding chemicals, allow your water to equilibrate before retesting, especially if you have been having problems with balance. This means letting the water circulate for a few hours, or retesting the next day for accurate readings. For best results, open all air valves and run the jet pumps.
• Total Alkalinity should be kept between 80-120 ppm.
• pH range is ideal between 7.2 and 7.6. Too low is acidic and will cause corrosion. Too high can result in scale formation.
• Never mix different chemicals together before adding to the spa water. Add them one at a time. Pre-dissolving granules in a plastic bucket of water is best.
• Make sure your water hardness is not too low. Adjust it before making final pH and TA adjustments. A good range for calcium hardness is 150-300 ppm.
• Check Total Alkalinity (TA) first, then adjust for proper pH range. Proper TA will buffer pH, that is, it will help to prevent pH fluctuations.
• Use fresh, high-quality test strips.
• Excessively high bromine or chlorine levels can result in false pH and TA readings.
• Change your spa water at least every 3 to 4 months, depending on the bather load.

Problem	Remedy
Bad source water or well water makes balancing difficult.	Reduce contaminants using a hose-end water fill filter, such as the PreFresh.

While most hot tub owners have no trouble getting their water into balance, there is great diversity in water types from region to region. Even within communities, someone could be on municipal water while their neighbor is on a well. Minerals and other elements in water can sometimes lead to difficulty getting pH and total alkalinity (TA) into balance. Luckily, no matter what trouble you’re having, we’re here to help!

Have questions about your water chemistry? Comment below for expert assistance!