About 12% of Florida residents—and millions of Americans nationwide—get their drinking water from private wells. Unlike public water systems, well water is not federally regulated after it leaves the well. Well owners are responsible for testing and, when needed, treating their water. This guide outlines common well water issues and the filtration and treatment options that can address them.
Why Well Water Is Different
Well water comes from groundwater (aquifers). It hasn’t gone through a municipal treatment plant, so it can contain bacteria, minerals, nitrates, metals, and other contaminants depending on geology, land use, and well construction. The only way to know what’s in your well is to test. State health departments and the EPA recommend testing at least annually for bacteria and periodically for a broader suite of contaminants (nitrates, metals, etc.). If you’re buying a home with a well, a full water quality test is standard during due diligence.
Common Well Water Issues and Treatments
Sediment and particles
Sand, silt, or rust can make water cloudy or cause wear on plumbing and appliances. Sediment filters (whole-house, at the point where water enters the home) are the first line of defense. They’re often used before any other treatment to protect downstream equipment.
Bacteria
Total coliform or E. coli can indicate contamination from septic, surface water, or other sources. Disinfection is required when tests are positive. Options include shock chlorination (for one-time or occasional treatment), continuous chlorination (chemical feed), or UV (ultraviolet) disinfection. UV doesn’t add chemicals but requires relatively clear water (sediment and hardness can reduce effectiveness), so sediment filtration and sometimes softening may be recommended first.
Hardness (calcium and magnesium)
Hard water causes scale and can reduce soap performance. Ion-exchange water softeners are the standard whole-house solution. They’re installed on the main line and require salt (or potassium) and periodic regeneration.
Iron and manganese
These can cause staining, metallic taste, and discoloration. Oxidation filters, greensand, or water softeners (for certain forms of iron) are common. Testing will show the form and level so the right treatment can be chosen.
Nitrates
Often linked to fertilizer, septic systems, or animal waste. Nitrates are a special concern for infants. Reverse osmosis at the kitchen tap is one of the most effective at-home options for nitrate reduction. Whole-house RO is possible but more complex and costly.
Arsenic, lead, and other metals
Concentration and form matter. Reverse osmosis and some activated carbon systems, when certified for the specific contaminant, can reduce many metals at the point of use. Testing confirms what you have and what treatment is appropriate.
PFAS and other emerging contaminants
PFAS have been found in some groundwater. Point-of-use RO or certified carbon filters that are certified to reduce PFOA/PFOS can help. Testing through a certified lab is needed to know if PFAS are present and at what level.
Typical “Stack” for Well Water
A common approach is to treat in stages:
- Sediment filter at the entry point to protect everything downstream.
- Softener (if hardness is an issue) for scale and comfort.
- Disinfection (UV or chlorination) if bacteria are a concern.
- Point-of-use RO or carbon at the kitchen for drinking and cooking, to address nitrates, metals, or PFAS that are better handled at one faucet.
Not every well needs every stage. Testing drives the design. A professional can help interpret results and recommend a sequence that matches your water and goals.
Testing and Maintenance
- Test at least once a year for bacteria and on a schedule for other parameters (nitrates, metals, etc.). After installing treatment, retest to confirm the system is working.
- Replace sediment filters, carbon cartridges, and RO filters and membranes on the manufacturer’s schedule.
- For UV: replace the lamp as recommended and ensure water is clear enough for the unit to work.
- For softeners: keep salt (or potassium) stocked and service the unit as needed.
Well water can be safe and great-tasting with the right testing and treatment. Starting with a solid test, then layering filtration and disinfection as needed, gives well owners confidence in their water quality for years to come.