The water-heater flush where you're standing there holding a bucket of scale. The third faucet cartridge in two years at the same house. The crusted aerators, the shower valve that won't stop dripping, and the question that comes as you're packing up: "While you're here — why does our water taste like a pool?"
Most plumbers answer those calls with a repair. A plumber who also tests the water answers with the repair and the reason, and lets the customer decide what to do about it. That is the whole playbook: no new lead source, no new trade, no separate sales team. Just a two-minute test on calls you're already running in city-water homes, and a clear offer when the number says something.
This page is the field side — the calls, the test, what to offer, how a first job runs, and how to plan your crew's install hours. If you're still deciding whether to add the line at all, start with adding water treatment to a plumbing business, the startup economics and state licensing breakdown and come back here.
The water calls already on your board
Nobody has to generate these leads. They're on the schedule, and the symptom is usually visible before the tech says a word.
| Call type | What you notice | What to test or check |
|---|---|---|
| Water-heater flush or replacement | Scale and sediment in the drain-down | Hardness test |
| Repeat cartridge or valve failures | Fixture history at the same address | Hardness test |
| Chlorine taste or odor complaint | The customer tells you | Total chlorine test, plus the city's CCR for chlorine vs. chloramine |
| New drinking-water request | "What do you have for the kitchen tap?" | TDS reading |
| Slow fixtures with crusted aerators | Visible scale on the parts you remove | Hardness test |
These are signs worth testing for, not diagnoses. The test result decides what you recommend. This guide covers municipal (city) water, which is what Aquonyx builds for.
The test is the conversation
The on-site routine takes two or three minutes at the kitchen tap: a hardness strip or titration, a total-chlorine reading, and a TDS meter. Before the visit — or on the tablet while the heater drains — pull the utility's Consumer Confidence Report for the disinfectant type, because chlorine and chloramine call for different carbon media and the CCR is where that answer lives. Our guides on how to test city water on site and how to read the city's Consumer Confidence Report cover the kit and the report line by line.
Then the rule that keeps this honest: no test, no recommendation. Write the numbers on the invoice, show the customer where they came from, and let them ask the next question. A hardness number the homeowner watched you take at their own tap does more than any brochure, and it costs you nothing if they say "not now."
What to offer first (and why)
Match the category of equipment to the test. Softening is for hardness. Carbon is for disinfectant taste and odor. Reverse osmosis is for a drinking-water request. Never sell a softener for a taste problem or a carbon filter for a scale problem — the test tells you which conversation you're in.
| Order | When the test and CCR point here | Product (type and spec) | Sizing |
|---|---|---|---|
| 1 | Hardness on city water | Diamond Soft metered ion-exchange softeners: 30K / 45K / 60K grain, 8% crosslink resin, Clack WS1 valve | Softener sizing calculator |
| 2 | Hardness plus a taste/odor concern, one footprint | The Diamond filter/softener combo: carbon under a softening bed, one tank, WS1 valve | Softener calculator for capacity |
| 3 | Taste/odor only | Black Diamond whole-home carbon: coconut-shell media for chlorine cities, catalytic media where the CCR shows chloramine; 1.0 / 1.5 / 2.0 ft³ | Home flow-rate (GPM) calculator and the carbon size guide |
| Add-on | Drinking-water request | Reverse osmosis, point-of-use | Per the model's documentation |
Start with softening on hard-water city routes. It's the job your crew already understands, and the test makes the case. Add carbon and RO as your techs get comfortable reading CCRs. Ion-exchange softening is the standard approach to hardness; activated carbon is the media class commonly used for chlorine taste and odor, with catalytic carbon specified where a utility uses chloramine; RO is a membrane process for point-of-use drinking water. Describe the equipment that way — by what it is — and let the model's documentation carry the specifics.
A first job, start to finish
Sample job
One water-heater call, run as a water job
Tick through it once on paper before the first live call.
0 of 9 checked
Then
That's the whole loop. The second job is the same loop with a tech who's done it once.
Plan the week before you sell the job
The common way a plumbing shop stumbles adding water isn't selling. It's selling more than the crew can install, and then watching a quoted job sit for three weeks while the customer cools off. Every input below starts blank. Use your own numbers. This is not a projection of earnings.
Your numbers · city-water jobs
Water calls → tests → installs: plan your week
Every input starts blank. The math is shown under the result.
Assumptions (editable)
Enter all 7 numbers to see your math. 0 of 7 entered.
Your numbers, not ours. This is arithmetic on the numbers you entered. It is not a projection of earnings, income or profit, and it is not a promise of results. “Installed-price total” is your price multiplied by your count. It comes before equipment, labor, financing fees, overhead and taxes, and actual results vary by market, pricing, licensing and effort.
If the install hours come out above what you've set aside, you have three honest options: add capacity, slow the offer rate, or line up a partner installer for overflow. Pick one before the first quote goes out.
Make it every call, not some calls
Operations beat enthusiasm. The shops that make this work do four small things:
- One trained champion plus a backup. Someone owns the water line, reads the CCRs, and answers the techs' questions. A backup so it doesn't stall on a vacation.
- A test kit on every truck. If the kit lives in one truck, only one truck offers tests.
- A job-ticket line: "Water tested: Y/N · result." It makes the offer a step, not a mood.
- Weekly counts of offers, tests, quotes and installs. Count offers, not just sales. If you aren't counting offers, you can't tell which step is leaking.
Maintain apartments or townhomes under contract as well? The multifamily guide covers in-unit installs and service routes. HVAC-led shops have their own version of this playbook in how HVAC companies add the line, and builders and remodelers get the walls-open version.
The honest questions
How the Aquonyx dealer program works for a plumbing company
- No application, enrollment or franchise fee.
- A one-pallet opening order to begin.
- Assigned wholesale pricing after approval, viewed in the dealer portal.
- Product and installation training during onboarding.
- The dealer portal for quotes, ordering, order tracking, installation scheduling and stock.
- The written dealer agreement governs territory and terms.
- Written Lifetime Limited Warranty terms provided to dealers.
- Homeowner financing: on completion of the dealer application, Aquonyx introduces you to its in-house homeowner financing program.
For the startup economics, licensing by state and what's actually incremental for a working contractor, read the startup economics of adding water treatment to a plumbing business.
Next heater flush, test the water. Apply to become a dealer — no fee, or see the systems first. Aquonyx is the manufacturer; dealers run their own businesses.
This guide covers municipal (city) water. Licensing varies by state; verify with your state board. Equipment is described by type and specification only — the model's documentation states what each system is designed to do.
About Aquonyx. Aquonyx builds city-water treatment systems for independent dealers. You buy from the maker. Articles are written and reviewed by the Aquonyx Technical Team; see how we source and check them.