Where spots come from
| Location | Usual cause |
|---|---|
| Shower glass, faucets | Dissolved solids left as tap water dries |
| Windows, cars, screen enclosures | Sprinkler overspray or salt air |
| Kettle, coffee maker | Minerals concentrating as water boils |
| Heavy scale on fixtures | Often a private well |
If your home uses a private well for household water, scale can be much heavier, because untreated groundwater still carries the hardness the city removes at its plant.
Treated isn't the same as mineral-free
The city's blend mixes lime-softened, nanofiltered and RO water. Softening removes hardness minerals, but treated water still carries some dissolved solids, and those can spot glass as they dry. The 2025 report doesn't give a single hardness or TDS figure, which is why a test at your tap is worth doing before buying anything.
Remember that the city's RO plant treats Floridan Aquifer water that starts with high mineral content. Blending is how the plant balances mineral content across its three processes, according to the report.
Softener vs. conditioner
A softener removes hardness; a salt-free conditioner leaves minerals in the water. On treated city water, neither may be needed. On a hard well, a softener is the usual answer. See salt-free conditioner vs. ion-exchange softener.
If someone recommends a conditioner or softener for spots, ask what hardness they measured. Without a number, it's a guess.
Spot-free drinking water
For glasses, kettles and ice, under-sink RO lowers total dissolved solids. See under-sink RO.
RO also helps coffee makers and kettles, which build mineral deposits from boiling water over time.
Prevention
- Squeegee shower glass after use.
- Aim sprinklers away from windows and screens.
- Descale kettles and coffee makers on schedule.
- Use a vinegar-based cleaner on fixtures, testing a hidden spot first.
- Dry cars after rinsing rather than letting them air-dry in the sun.
Businesses
For a restaurant dishwasher, ice machine or car wash rinse, spotting and scale limits come from the equipment maker. Living Water's ion-exchange softening plants are sized after a test and a look at those specs.
Test before buying
Jorge measures hardness and TDS at your tap. Call, text or WhatsApp (305) 793-5974. Related: water softeners in Deerfield Beach.
Updated 2026-10-17 · Living Waters · Jorge Canela, Water Quality Specialist