Pool Sense
678-428-7763 Request a site assessment

Water chemistry

Water chemistry and code compliance for commercial pools

Free chlorine, pH, alkalinity, calcium, and stabilizer held to the Georgia DPH 511-3-5 code and your county's rules, with the records to prove it to an inspector.

Rectangular community pool with a wood-sided pool house and an iron fence

Measured to the decimal, held between visits

Commercial pool chemistry is not hard to get right on the day of a visit. It is hard to keep right for the six days in between, when two hundred residents, a thunderstorm, and a 97-degree afternoon each pull the water in a different direction.

Our answer has two parts. On the visit, a LaMotte SpinTouch photometer reads the water: free chlorine, combined chlorine, pH, total alkalinity, calcium hardness, cyanuric acid, phosphates, and salt where it applies. The technician dose is computed from that reading and the pool's measured volume, not from a strip and a guess.

Between visits, the PoolCop controller reads pH and ORP (the sanitizer's oxidizing strength) continuously and feeds acid and chlorine to setpoint. PoolSense Intelligence records every reading, projects free chlorine, alkalinity, and stabilizer forward from the last verified test, and flags the pool the moment a number leaves its band. The SpinTouch result at the next visit grades the projection, so the model gets better at that specific pool over time.

Code compliance is a records problem

Georgia's Chapter 511-3-5 and the county rules that sit on top of it are specific: chlorine and pH ranges, a trained operator on record, daily logs, a visible main drain, tested safety equipment. Most violations we see at pools we take over are not chemistry violations. They are missing records.

So the records are automatic. Every visit's test and every chemical added is logged. The pool's log book is printed from that record, and a QR code on the log book opens the full history from day one. When the inspector comes, the book is current. When the inspector has a question, they can call us instead of the property manager.

We keep pools to the counties we work in most: Forsyth, Cobb, Paulding, and DeKalb rule sheets are in the platform, and the state code covers the rest. Read the board's guide to the code.

7.2–7.8Georgia pH range during operation
≥1.0 ppmFree chlorine minimum (2.0 ppm when stabilized)
≤90 ppmCyanuric acid ceiling; we target 30–50

Values summarized from Georgia DPH Chapter 511-3-5 and county rules. Your county's current rule sheet governs.

Questions boards and managers ask us

What are the Georgia code limits for a commercial pool?
Chapter 511-3-5 of the Georgia DPH rules sets the ranges: free chlorine of at least 1.0 ppm (2.0 ppm when the pool is stabilized with cyanuric acid), pH between 7.2 and 7.8, combined chlorine under 0.4 ppm, cyanuric acid no higher than 90 ppm, and the main drain visible from the deck. Counties add their own rules on top. The board's guide to the code.
How often does the health department inspect?
Seasonal pools are inspected at least once per season and year-round pools at least twice a year, plus complaint-driven visits. The inspector checks chemistry on the spot, the daily log, the trained-operator certificate, and safety equipment.
What test equipment do you use?
A LaMotte WaterLink SpinTouch photometer on every visit, which reads free and total chlorine, pH, alkalinity, calcium hardness, cyanuric acid, phosphates, copper, and salt. The controller's pH and ORP probes read continuously between visits, and the SpinTouch result is used to verify the probes are not drifting.
Why does pH matter so much?
Chlorine works far better at 7.4 than at 8.0. High pH also scales heaters and plaster; low pH corrodes them. Under Georgia code, pH outside the range during operation is an imminent health hazard, which means the pool closes until it is corrected. Automatic acid feed on the controller keeps it in range between visits.
What is the Langelier Saturation Index and why do you talk about it?
It is a single number, from about minus one to plus one, that says whether the water wants to dissolve plaster and metal (negative) or deposit scale (positive). We compute it on every test from pH, temperature, alkalinity, calcium, and stabilizer, and we adjust toward zero. It is the difference between a plaster surface that lasts twelve years and one that lasts six.
Do you handle the daily log the inspector asks for?
Yes. Test results, chemicals added, and equipment checks are logged at every visit and printed to a log book at the pool. A QR code on the log book opens the full history from the day we started, so an inspector can see months of records without a phone call.
Can you fix a pool that has been mismanaged?
Usually. High cyanuric acid, scale, staining, and phosphate loads all have known fixes, though some of them take a partial drain. The assessment tells us which. We will not promise a date for clear water until we have a SpinTouch reading.

Related

Chemistry is where most inspection findings come from. See how we handle it for your property type, and where we work.

Get in touch

Request a site assessment

Tell us about the property and we will schedule a walkthrough: equipment review, a SpinTouch chemistry baseline, and a candid read on what the current program is missing.

Free, no obligation. We respond within one business day. By submitting you agree to be contacted about your inquiry.

Call Request assessment