Expert Tips for Testing Your Swimming Pool Water
One of the most important responsibilities that comes along with being a pool owner is maintaining the proper water chemistry to ensure your investment is swimmer-friendly.
The first step in protecting your pool from unwanted bacteria that can cause discoloration, algae growth, and health risks is routine water testing.
Knowing where to begin to accurately and correctly test your water can be difficult, especially for new pool owners. If you need some additional insights, take advantage of these tips from LinerWorld’s pool experts!
Why Testing Your Pool Water Matters
Testing your pool water frequently ensures proper sanitation, optimal pool performance, and ongoing cost savings.
Imbalanced chemicals — either too much or too little — put unnecessary strain on your pump and filter and can damage your above ground pool liner, leading to more frequent repairs and replacements.
On the flip side, proper sanitation and chemical balance kills bacteria, viruses, and algae, which prevents damage to your pool liner and accessories. It also minimizes health risks to eyes and skin while swimming.
How Often Should You Test Your Pool Chemical Levels
In general, it’s recommended to test your pool water at least once a week.
More frequent testing may be needed if you and your family are using the pool on a regular basis or there were storms, chemicals added, or you’re noticing issues such as algae growth.
Step-by-Step: How to Test Pool Water
Testing your pool water chemistry may seem intimidating, especially to new pool owners, but it’s not hard. Let’s walk through it step by step.
Collect Your Water Sample
Use a clean plastic container (that’s only for the pool) and scoop up some water. For the most accurate results, we recommend scooping water from about 18 inches below the surface and avoiding the areas around jets, skimmers, or ladders.
Perform the Test
Now it’s time to test the sample. You can either use test strips, liquid test kits, or digital testers.
Test Strips:
Dip your water testing strip in water per the manufacturer’s instructions (usually about 2–3 seconds). Do not shake it.
After about 30-60 seconds, you’ll see the colors develop. Compare the results with the chart on the bottle.
Liquid Kits:
Start by filling your test tube to line with pool water. Then add your drops as directed.
After adding the drops, put on the cap and shake the test tube gently. Compare the color change with the chart provided with the kit.
Digital Testers:
Dip your digital probe or insert the test strip. Then, read your digital results.
Key Chemical Ranges To Watch For
These can vary slightly, but here are general guidelines for proper pool water chemistry.
| Parameter | Ideal Range |
|---|---|
| Free Chlorine | 1.0 – 3.0 ppm |
| pH | 7.4 – 7.6 |
| Total Alkalinity | 80 – 120 ppm |
| Calcium Hardness | 200 – 400 ppm |
| Cyanuric Acid | 30 – 50 ppm (for chlorine pools) |
Pro Tips When Testing Your Pool Water
At LinerWorld, we know a thing or two about pools. We’ve put together some helpful tips to help make testing your pool water easier, faster, and more efficient. Use these tips to spend more time swimming and less time maintaining your pool!
Integrate Technology Into Your Water Testing Routine
You can download a wide variety of swimming pool apps to make testing your water chemistry and maintaining your pool a breeze.
There are apps that will read your testing strips, provide customized treatment plans, track water readings, and so much more. Even your phone’s built-in apps, such as Reminders and Notes, can also be helpful for staying on track with water testing and monitoring chemical ranges over time.
Swimming pool apps are perfect for beginners who may need added instruction or for seasoned pros who might want to save time when performing routine pool maintenance. Either way, integrating technology into your testing routine is a great way to find and track accurate information about your water chemistry.
Always Test Chlorine, pH, Alkalinity, and Calcium Levels
There are a lot of specific parameters you can test your swimming pool’s water for, but what should be your main priorities as an owner? Routinely analyzing chlorine, alkalinity, calcium and pH levels should be your main focus.
These four factors are directly impacted by pool usage, weather, and the changing of seasons. In order to maintain a clean, swimmer-friendly pool, these are the levels that should always be tested on a weekly basis, especially after out-of-the-ordinary storms or during a seasonal change.
Always Test Chlorine, pH, Alkalinity, and Calcium Levels
There are a lot of specific parameters you can test your swimming pool’s water for, but what should be your main priorities as an owner? Routinely analyzing chlorine, alkalinity, calcium and pH levels should be your main focus.
These four factors are directly impacted by pool usage, weather, and the changing of seasons. In order to maintain a clean, swimmer-friendly pool, these are the levels that should always be tested on a weekly basis, especially after out-of-the-ordinary storms or during a seasonal change.
Never Use Testing Strips That Are From a Previous Season
One of the biggest mistakes we see pool owners make when it comes to water testing, is using test strips that are from a previous swim season. Typically speaking, testing strips have a shelf life for one season before the chances of a false reading increases greatly.
Old, out-of-date strips should be properly disposed of and replaced with new ones in order to retain accurate readings, especially for chlorine.
If you’re using a digital tester, make sure you follow manufacturer guidelines for replacements and cleaning to ensure your accurate results year after year.
Wait Before Reading a Test Strip
Although you may see your test strip change colors almost instantaneously after dipping it into your pool’s water, it’s important that you wait the appropriate amount of time (usually 20-30 seconds) before reading the results, per the manufacturer guidelines.
Waiting the full designated time frame allows for all levels and colors to accurately develop, eliminating the chances of a false reading and wrong treatment of your pool’s water.
Another common error that many pool owners make after the colors develop, is not correctly corresponding the colors to their correct match. If you’re unsure of a color reading or it’s unclear, take another sample and wait the suggested time for the results to re-appear.
Test Chlorine Levels in the Morning
LinerWorld’s pool experts recommend testing your water for its chlorine levels in the morning to avoid false readings. If possible, do the test around the same time every time you check your water to ensure consistency across readings.
The ultra-violet rays that are emitted by the sun have a huge impact on your swimming pool’s water chemistry, specifically when it comes to chlorine. UV light causes chlorine to dissipate, altering its levels and impacting testing results.
If the early daytime hours don’t fit into your maintenance schedule, adding cyanuric acid is a great alternative to provide a stabilizer for chlorine, minimizing the negative effects of the sunlight.
Maintain Your Pool All Season Long With LinerWorld
Remembering these tips and following the instructions from your pool chemical manufacturers are the best ways to ensure an accurate test and treatment every time.
If you have questions about testing your pool water or are looking for the latest in pool accessories, including unique pool liners, pool covers, pool floats, and more, the above ground pool experts at LinerWorld have your back. We have everything you need to make a splash and enjoy your pool this summer!
Last Updated June 30, 2025
