Pool water testing log: what to record for inspections
A practical guide for pool service companies and technicians: what a complete water quality log looks like, how to fill it in without mistakes, and how to have it ready whenever an inspector asks.
Why a testing log matters
Public, commercial and community pools are usually required by local health authorities to keep records of water quality checks, chemicals used and incidents. Requirements vary by country and region, so always check the rules that apply to each site.
In practice, the pool service company is the one filling in that log. If it is incomplete, unsigned or does not match the chemicals used, the service provider shares the consequences.
Common parameters and reference ranges
| Parameter | Typical range | Minimum frequency |
|---|---|---|
| pH | 7.2 – 7.8 | Every visit / daily |
| Free chlorine | 1 – 3 mg/L (ppm) | Every visit / daily |
| Combined chlorine | ≤ 0.5 mg/L | Every visit |
| Cyanuric acid | 30 – 75 mg/L | Weekly if stabilised chlorine is used |
| Turbidity / clarity | Main drain visible | Every visit |
| Water temperature | Per site requirements | Daily on heated pools |
What each log sheet should include
Identification
- Owner and site address
- Pool (name, volume, treatment type)
- Service company and responsible technician
Readings
- Date and time of each test
- pH, free and combined chlorine, clarity and temperature
- Water replaced
Chemicals and incidents
- Chemicals added and quantities
- Incidents, closures and corrective actions
- Product identification
Sign-off
- Signature of the technician or service manager
- Monthly review and close-out
- Records kept available for inspectors
Mistakes inspectors notice
Gaps
Missing days or empty columns. If it isn't written down, it didn't happen.
Copied values
Identical readings day after day look fabricated. Record what your test kit actually shows.
No signature
Each check should be signed by the technician or manager — never by the client.
No corrective action
An out-of-range reading must be followed by what was done to fix it.
Keeping it up to date without paperwork
- 1
Test at every visit
Record readings on your phone at the pool, with automatic date and time.
- 2
Log chemicals and incidents
Every dose and every issue is linked to the visit.
- 3
Sign the report
The technician or manager signs the visit in the app.
- 4
Export the monthly PDF
Pool Service Hub builds the monthly log as a PDF, ready to print or show an inspector.
Keep reading: Report and contract template · How to keep water clean · Maintenance guide
Frequently asked questions
Do I need a water testing log for a residential pool?+
Usually not by law, but keeping one protects you if a client disputes the condition of the water. Public and community pools typically do need one.
How long should I keep the records?+
It depends on local regulations. Keeping them for several seasons is a safe practice.
Who signs the log?+
The technician who did the tests or the service manager. The client does not sign it.
Is a digital log valid?+
In most places yes, as long as it contains all required data, is signed and can be shown to inspectors, for example as a printed PDF.
Generate your monthly water testing log as a PDF in one click
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