Pool pH Levels: What They Should Be (and How to Adjust Them)

A low pH reading can leave you wondering how much product to add, or if you even have the right one in the first place. Pool pH levels affect how well your chlorine works and how comfortable the water is for swimming. If your latest test shows a reading that’s too high or too low, we’ll help you choose the right treatment and get your water back in balance.

Key Takeaways

• Aim for 7.4. Keep pool pH between 7.4-7.6.
• Check alkalinity, too. It helps keep pH from fluctuating.
• Measure each dose. Use your test results, pool volume, and product directions.
• Retest before adding more. Give the treatment time to circulate.

What Are Pool pH Levels?

pH measures how acidic or basic water is on a scale of 0–14. Seven is neutral; lower numbers are acidic, and higher numbers are basic (i.e., less acidic).

For pools, we recommend 7.4-7.6, with 7.4 as the ideal target. Total alkalinity is a different measurement: it tells you how well the water resists changes in pH. Our Pool House guide explains how these levels work together.

Why pH Levels Matter for Your Pool

High pH makes chlorine less effective at killing germs, so keeping your pool sanitary requires checking both readings. It can also contribute to cloudy water and calcium scale.

Low pH can irritate swimmers’ eyes and skin and contribute to corrosion or surface damage. Keeping water balanced helps protect your pool equipment, including the heater you count on for cooler swim days.

Signs Your Pool pH Is Too Low

Stinging eyes, irritated skin, or corrosion on metal components can be clues, but they have other possible causes. A water test is the way to confirm low pH. Be advised that clear water can still have a reading below 7.4, so don’t wait for a visible problem to test!

Come in for a free water test at your local Pinch A Penny.

How to Raise pH Levels in Your Pool

Before reaching for a swimming pool pH increaser, check your results and follow these steps:

1. Test pH and total alkalinity. Use fresh testing supplies and follow the kit’s directions. Correct low alkalinity first, then retest pH; that adjustment may raise it, too. You can also bring a sample to a Pinch A Penny location for a free water test.
2. Work out the dose. Use the product’s directions for your pool’s gallon count and current reading. A larger scoop won’t necessarily get you swimming sooner.
3. Add the product as directed. Keep swimmers out, run the circulation system as instructed, and wear the protective gear listed on the label. Never mix pool chemicals together.
4. Circulate and retest. Wait the label’s specified time before checking pH and alkalinity again. Add another measured dose only if needed.

Be sure to read our guide to balancing pool water to learn about other levels to check alongside pH.

Choosing the Right Product to Increase Pool pH

Our Suncoast pH Plus is designed to raise low pH. An alkalinity increaser is for low total alkalinity and can also raise pH. If both readings are low, most of the time you will follow the alkalinity increaser’s label first, then retest both. If pH is still below range, use pH Plus as directed. In some cases, when alkalinity is extremely low, you may need to add pH Plus first, so we recommend getting a free water test at your local store to be sure.

Not sure what your pool needs next? Bring us a water sample, and we’ll help you figure it out!

How to Lower High pH Levels in Your Pool

For pH above 7.8, a reducer such as Suncoast pH Minus or Pinch A Penny’s Salinity Acid can lower the reading. These products also lower the alkalinity.

Follow the label’s dosage and application instructions, including eye and skin protection. Never mix acid with chlorine. Allow the water to circulate for the directed time, then retest before adding more.

Maintaining Optimal pH Levels Year-Round

Test pH and chlorine at least once a week when your pool is in use, with extra checks after heavy rain or chemical adjustments. Keep a record of readings and doses so you can spot recurring changes more easily. If you bring a sample to a Pinch A Penny location, we keep a record of all of your tests.

Continue testing during cooler months if your pool stays open. After all, fewer swimmers or pool activity doesn’t mean the water stops changing.

FAQs About Pool pH Levels

What Causes Low pH in a Swimming Pool?

Too much pH reducer or acidic sanitizers, such as trichlor tablets, can lower pH. Low total alkalinity leaves the water less able to resist those changes. Test both pH and alkalinity. If alkalinity is low, use an alkalinity increaser according to its label, then retest pH before adding pH Plus; raising alkalinity may bring pH up, too.

Why Does My Pool’s pH Keep Rising?

pH rises as dissolved carbon dioxide escapes the water. Splashing and water features speed up that process. High alkalinity can also contribute to recurring pH rise, so check both readings.

Why Won’t My Pool’s pH Go Down After Adding Muriatic Acid?

High alkalinity may mean the dose was insufficient, or the acid may need more time to circulate. Very high chlorine can also interfere with some pH tests. Have your results checked before adding more acid.

Can I Use Baking Soda to Raise Pool pH?

Baking soda primarily raises total alkalinity and usually has a smaller effect on pH. It can help when alkalinity is low, but it isn’t interchangeable with a pH increaser made with soda ash.

How Long Should I Wait to Swim After Adjusting pH?

Follow your product’s waiting period and circulation instructions. Before anyone gets in, retest to confirm pH and sanitizer levels are within their recommended ranges. The clock alone can’t tell you the water is ready!

Get Help Balancing Your Pool at Pinch A Penny

If your readings keep changing, stop by your local Pinch A Penny for a free water test. We’ll explain the results and recommend what your pool needs, so you can spend less time puzzling over test colors and more time enjoying your perfect water.