Where the minerals come from
The Biscayne Aquifer is limestone, so the City's raw well water is naturally rich in calcium. The 2025 report says the City uses traditional lime softening and other chemicals to remove odor, minerals and particles, then filters the water. What remains, including sodium at 30.0 ppm and other dissolved solids, can still leave marks on glass and chrome when droplets dry. The report does not publish a hardness number, so your tap test is the measure that counts.
Spots or scale?
- Crust on aerators and shower heads: calcium scale, a hardness sign.
- Film on glass that vinegar removes: minerals, often hardness.
- Spots on cars or windows near sprinklers: irrigation well water.
- Orange or brown: iron, a separate issue; see orange stains.
Low-cost fixes first
- Squeegee shower glass after each use.
- Soak aerators and shower heads in vinegar.
- Use rinse aid in the dishwasher.
- Use RO water for kettles, coffee makers and glassware.
- Consider a softener only if your test shows meaningful hardness.
Softener vs. conditioner
An ion-exchange softener removes hardness minerals. A salt-free conditioner changes how scale forms but leaves the minerals, so spots usually remain. For a business with dishwashers, ice machines or boilers, a properly sized softening plant is the usual answer. See water softeners in North Lauderdale and salt-free vs. ion-exchange.
Appliances and treatment changes
Tankless heaters, kettles and coffee machines show scale first, because heat speeds it up. Check the manufacturer's hardness guidance against your test result. The City's report also says engineers have been consulted on the design of a nanofiltration plant; if treatment changes in future years, the mineral content at your tap could change too, and a retest would show it.
What the numbers mean
Hardness is usually given in grains per gallon or ppm as calcium carbonate; TDS is total dissolved solids in ppm. A low hardness reading with a moderate TDS means spots come from other minerals, which a softener will not fix but RO drinking water will. A high hardness reading, typical of a private well, is when a softener earns its place. Jorge explains both numbers next to each other.
Measure it
Jorge tests hardness and TDS at your tap free and tells you which fix makes sense. Call, text or WhatsApp (305) 793-5974.
Updated 2026-10-17 · Living Waters · Jorge Canela, Water Quality Specialist