Every test result for one pool, over time
When technicians record water chemistry on a visit (see complete a visit), those readings build a history for that specific body of water. The Chemistry Trends section charts that history — one small chart per parameter, each with its target range shaded behind the line — so a pool that has been drifting for a month is obvious at a glance.
Chemistry Trends is a web-dashboard view. In the mobile app, technicians see a "Recent Readings" card with the last few visits' numbers side by side — there are no trend charts on the phone.
Where to find it
- On a body of water's page — open a customer or service location, click the pool (spa, hot tub, water feature) to open its page, and the Chemistry Trends section sits right under the basic details. It is always visible; there is nothing to expand.
- On a service location's page — a Chemistry Trends section appears after the Bodies of Water list. If the location has more than one body of water, a row of pills lets you switch between them; each pool is charted on its own.
Readings are never averaged across two bodies of water — a spa's 102°F and a pool's 84°F would be meaningless together. You always look at one body at a time.
The section header reads "Every test result over time, against its target range", followed by the count of readings in view ("14 readings"). The date-range presets sit at the right of that header.
Pick a date range
The presets on the right of the section are Last 30 Days, Last 90 Days, and All Time. It opens on Last 90 Days. Every chart and the reading count follow the range.
- If nothing was tested in the range but the pool has been tested before, you get "No readings in this range" with a nudge to widen it.
- If the pool has never been tested, it reads "No water tests recorded yet" — chemistry appears once a technician logs a test on a completed visit.
The latest test at a glance
Above the charts, a strip of chips shows the most recent test — "Latest test · Aug 24, 2026" — with one chip per parameter that was measured. Chips are tinted green when the value is inside its target band and amber when it is outside, so an out-of-range pool reads instantly. The LSI chip additionally shows its status word: Balanced, Acceptable, Corrosive, or Scaling.
Choose which parameters to chart
Under the chips is a row of parameter pills. Click one to add or remove its chart. The selection starts on pH, Free Chlorine, Total Alkalinity, and LSI (Saturation Index), and your choice is remembered in your browser for the next pool you open.
- A pill greyed out means that parameter was not tested in this range. Selecting it anyway shows a "Not tested in this range" placeholder in its slot.
- The list follows your water chemistry settings: parameters you hid are not offered, renamed parameters use your label and unit, and your own custom measurements (ORP, borates, and so on) are chartable too.
- LSI is always available on top of the configured list, because it is calculated rather than measured.
Each parameter gets its own chart rather than sharing one — pH around 7.5 and salt around 3,000 ppm cannot share a scale honestly.
Reading a trend chart
- The green shaded band behind the line is the target range, labelled under the parameter name — for example "Target 7.4–7.6" or "Target under 0.5 ppm".
- The chip in the top right of each chart is the latest value for that parameter: green when in the band, amber when out.
- A visit where that parameter was not measured leaves a gap in the data; the line bridges it rather than dropping to zero.
- Hover any point for the exact value on that date.
The target ranges used by the charts are:
| Parameter | Target band on the chart |
|---|---|
| Free Chlorine | 1 – 4 ppm |
| pH | 7.4 – 7.6 |
| Total Alkalinity | 80 – 120 ppm |
| Combined Chlorine | under 0.5 ppm |
| CYA (Stabilizer) | 30 – 50 ppm |
| Calcium Hardness | 200 – 400 ppm |
| TDS | under 2,000 ppm |
| Salt | 2,700 – 3,400 ppm |
| Phosphates | under 100 ppb |
| Bromine | 3 – 5 ppm |
| LSI (Saturation Index) | 0 – 0.3 |
These bands are fixed reference ranges drawn on the chart — they are not editable and they do not trigger anything. The ranges that DO raise an alert are the per-parameter min/max in Technician Alerts → Alert Settings, which are deliberately wider (pH 7.0–8.0 by default). A reading can sit outside the chart's green band without being alert-worthy. See technician alerts.
Temperature has no target band — it is charted so you can see the season, not judged against a range.
The LSI chart
LSI (the Langelier Saturation Index) is calculated automatically from the built-in readings whenever chemistry is recorded — technicians do not enter it. Its chart is drawn a little differently:
- Two bands: the green ideal band from 0 to 0.3, and a wider amber acceptable band from −0.3 to 0.5.
- Every dot is coloured by that reading's status — green Balanced, amber Acceptable, red Corrosive, purple Scaling — so a run of corrosive water stands out even before you read the axis.
- Hovering a point names the status alongside the value.
Custom measurements do not feed the LSI calculation — see water chemistry settings.
What Chemistry Trends does not do
- It is not in the technician mobile app. Techs get the "Recent Readings" card on the completion screen — the last visits' numbers side by side — not charts.
- No export or print. There is no CSV, PDF, or image download of the charts, and they are not attached to service reports or customer emails.
- No alerts from the chart. The target bands are reference only. Out-of-range alerting lives in Technician Alerts, which is off by default until you turn the chemistry detector on.
- No dosing recommendations. The trend charts report what was measured; deciding what to put in the pool is still the technician's call (see complete a visit).
- No editable target bands, and no per-pool overrides of them.
- No comparison across pools — you cannot overlay two bodies of water on one chart, or chart a whole customer's or route's chemistry together.
- Not on the customer portal. Customers see their visit's readings on service reports and in the portal when those are enabled; the trend charts are internal.
For the money side of the same pool — what chemicals went in, what they cost, and what was billed — the Chemical Usage & Cost section further down the same page covers it. See chemical usage and cost analytics.
Frequently asked questions
Where do I see a pool's chemistry history as a chart?
Open the body of water's page (from a customer or service location, click the pool). The Chemistry Trends section is right under the basic details and is always visible — nothing to expand. The service location page has the same section, with a pill switcher when the location has more than one body of water.
Can my technicians see the trend charts on their phone?
No. Chemistry Trends is on the web dashboard. On the mobile completion screen technicians get a "Recent Readings" card showing the last visits' numbers side by side (including LSI), which is enough to spot a trend poolside, but there are no charts in the app.
Can I change the target ranges shown on the charts?
No — the green target bands are fixed reference ranges. The ranges you can edit are the alert ranges in Technician Alerts → Alert Settings, which decide when a reading raises a "Water chemistry out of range" alert. They are wider than the chart bands on purpose, so a reading outside the green band is not automatically an alert.
Why is a parameter greyed out in the picker?
It was not tested on any visit inside the date range you have selected. Widen the range, or check whether that parameter is hidden or optional in your Water Chemistry settings.
Can I export or print the chemistry charts for a customer?
No. There is no export, download, or print of the trend charts, and they are not attached to service reports. Customers can see the readings from an individual visit on their service report and in the customer portal when those are turned on.
Why does the LSI chart have two shaded bands?
The green band (0 to 0.3) is the ideal range and the wider amber band (−0.3 to 0.5) is the acceptable range. Each dot is also coloured by its own status: Balanced, Acceptable, Corrosive, or Scaling.