Test your water
Use a reliable test kit at least twice a week during swim season to capture baseline readings before making adjustments.
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Enter your pool details and current readings to get precise chemical dosing recommendations.
Step 1 — Pool Volume
Step 2 — Select Chemical
Step 3 — Current & Target Levels
Chlorine Source
Pool Surface
CYA Source
Recommended Dosage
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Step 4 — Pool Type
Reference
Use this reference chart to understand where your readings should fall.
| Parameter | Ideal Range | Too Low | If Too High |
|---|---|---|---|
| Free Chlorine | 1–3 ppm | Below 1 ppm | Above 5 ppm |
| pH | 7.2–7.6 | Below 7.2 | Above 7.8 |
| Total Alkalinity | 80–120 ppm | Below 80 ppm | Above 150 ppm |
| Calcium Hardness | 200–400 ppm | Below 150 ppm | Above 500 ppm |
| Cyanuric Acid (CYA) | 30–50 ppm | Below 30 ppm | Above 100 ppm |
Tips
Follow these steps in order for stable, comfortable pool water.
Use a reliable test kit at least twice a week during swim season to capture baseline readings before making adjustments.
Stabilize total alkalinity between 80–120 ppm before changing pH or sanitizer levels to prevent pH bounce.
Keep pH between 7.2 and 7.6 for swimmer comfort and maximum chlorine effectiveness.
Apply shock treatment after heavy use, rainstorms, or algae signs to restore a reliable free chlorine residual.
Maintain free chlorine at 1–3 ppm indoors, or 5–7% of CYA outdoors when stabilizer is present.
Keep calcium hardness between 200–400 ppm to protect plaster surfaces and prevent scale buildup.
FAQs
For most residential pools, test the water 2–3 times per week during the swimming season. Check more frequently during hot weather, after heavy pool use, or following significant rainfall. At a minimum, monitor free chlorine and pH regularly, while alkalinity, calcium hardness and cyanuric acid (CYA) can be checked less frequently unless you notice a water-quality issue.
Rapid chlorine loss is often caused by strong sunlight, heavy pool use, high organic contamination, or algae growth. Low or unbalanced cyanuric acid (CYA) can also allow UV light to break down chlorine more quickly in outdoor pools. If chlorine levels keep dropping despite regular dosing, test the water and check for algae, debris and other sources of chlorine demand rather than simply adding more chlorine.
No — never mix pool chemicals together. Adding incompatible chemicals together can cause dangerous reactions. Add chemicals separately, with the circulation system running, and follow the product label for the correct dosage, application method and waiting time before adding another chemical or using the pool. Some products may also require pre-dilution, while others should never be diluted, so always follow the manufacturer's instructions.
Cloudy pool water is usually linked to poor filtration, unbalanced water chemistry, excessive swimmer load, fine debris, or the early stages of algae growth. Start by testing the water and checking the pH and chlorine levels, then make sure the filter and circulation system are operating properly. If the chemistry is balanced but the water remains cloudy, the filter may need cleaning or longer filtration, and persistent cloudiness may indicate a contamination or algae problem.
The most reliable way to lower high cyanuric acid (CYA) is to replace some of the pool water with fresh water. CYA does not normally decrease quickly through filtration or standard chemical treatment. After partial draining and refilling, retest the water and adjust chlorine levels accordingly. If CYA is consistently high, consider reducing your use of stabilized chlorine products such as trichlor or dichlor and use an appropriate unstabilized chlorine source when suitable for your pool.