Common places it shows up
- Frameless glass shower enclosures, which are common in renovated bathrooms.
- Faucet aerators and rain showerheads that slowly clog.
- Dishwasher film on glassware.
- Kettles, coffee machines and ice makers.
- The water heater, out of sight, where scale reduces efficiency.
Why spots happen even with softened water
NMB Water's 2025 report describes lime softening or nanofiltration for Biscayne Aquifer water and reverse osmosis for Floridan Aquifer water, blended before distribution. That reduces hardness but does not remove every dissolved mineral. Any water that evaporates on glass leaves something behind, and in a humid bathroom water dries slowly enough to mark the surface. Outdoor glass is a separate case: if a property irrigates from a well, sprinkler overspray can carry untreated minerals and iron onto windows and railings.
Measure before you buy
NMB's report does not publish a single hardness number for your building. A free test from Jorge puts a number on hardness and dissolved solids at your own faucet. Low numbers point to a cleaning routine; higher numbers make a softener worth discussing, at least for a house or townhome.
Softener or conditioner, if you have the main line
| Ion-exchange softener | Salt-free conditioner | |
|---|---|---|
| Hardness minerals | Removed and replaced with sodium or potassium | Remain in the water in altered form |
| Glass spots | Greatly reduced | Can still form as water dries |
| Fits a condo unit? | Rarely | Rarely, for the same reason |
| Upkeep | Salt and service | Media replacement |
See salt-free vs. ion-exchange.
Protecting appliances
Spots on glass are cosmetic. Scale inside a water heater, dishwasher, ice maker or espresso machine is a maintenance cost, because mineral layers reduce heating efficiency and wear parts. In a house or townhome with a tank heater, measured hardness may justify softening for that reason alone. In a condo, the practical protection is regular descaling of small appliances and periodic heater flushing, done according to each manufacturer's instructions.
A condo routine that works
- Squeegee the shower glass after every use; it is the single most effective habit.
- Run the bathroom exhaust fan during and after showers to speed drying.
- Soak aerators and showerheads in white vinegar every few months.
- Use rinse aid in the dishwasher.
- Flush your unit's water heater on a schedule; NMB's report recommends flushing the heater and household plumbing at least twice a year.
Book
Call, text or WhatsApp (305) 793-5974. Jorge measures hardness free and tells you whether equipment is worth it, or whether the routine above will do.
Updated 2026-10-17 · Living Waters · Jorge Canela, Water Quality Specialist