What causes the spots
When water dries, its dissolved minerals stay behind. Calcium and magnesium form the white crust on aerators and showerheads and the cloudy film on glass doors. Heat speeds it up, which is why water heaters, kettles and coffee makers build scale fastest.
Not every white mark is hardness. Mineral spots from sprinklers on windows and screens may come from an irrigation well, and those often have an orange tint from iron. See orange and rust stains in Kendall.
Where Kendall's water stands
WASD's 2025 Water Quality Report says Orr plant water "receives lime treatment to reduce hardness" before it is disinfected and filtered. That is a real benefit, but it does not bring hardness to zero. How much remains at your tap is the number that matters, and it is quick to measure.
Softener or conditioner?
| Ion-exchange softener | Salt-free conditioner | |
|---|---|---|
| What it does | Removes calcium and magnesium | Aims to change how minerals behave so they scale less |
| Spots on glass | Greatly reduced because minerals are gone | Minerals remain in the water, so drying spots can still form |
| Upkeep | Salt or potassium, regeneration | Media replacement per manufacturer |
Read salt-free conditioner vs. ion-exchange softener for the details. Living Water installs ion-exchange softeners.
Scale and your appliances
Spots are the visible part. Inside the house, scale also builds in places you cannot see: tank water heaters, tankless heater heat exchangers, dishwashers, coffee makers and ice machines. Signs include a heater that crackles, slower hot water, and appliances that need descaling more often than the manual suggests. A tankless water heater manufacturer may also recommend water treatment in hard water areas; check your model's manual. These are good reasons to know your hardness number even if the spots do not bother you.
Cheap habits that help
- Squeegee shower glass after use.
- Soak aerators and showerheads in white vinegar periodically.
- Use a rinse aid in the dishwasher.
- Flush the water heater per the manufacturer's schedule.
If you are doing all that and still fighting scale, a softener in Kendall may be worth a look. For cost factors, see water softener cost in Kendall.
Measure it free
Jorge tests hardness at your tap and tells you plainly if a softener would change anything. Call, text or WhatsApp (305) 793-5974.
Updated 2026-10-17 · Living Waters · Jorge Canela, Water Quality Specialist