Match the process to the problem.
Compare capabilities and limitations. A treatment category is not a product recommendation.
Ion-exchange softening
- Useful for
- Dissolved calcium and magnesium hardness
- Limits
- Does not disinfect or remove every contaminant; adds sodium or potassium depending on regenerant.
- Test first
- Hardness, iron, manganese, flow and daily use
- Maintenance
- Salt, regeneration water, model-specific cleaning
- Certification
- NSF/ANSI 44; verify the exact model and claim
Activated carbon
- Useful for
- Specific taste, odor and organic-chemical reduction claims
- Limits
- Does not soften water or reliably remove all dissolved salts; performance is contaminant-specific.
- Test first
- Target chemical, disinfectant, contact time and flow
- Maintenance
- Timely media or cartridge replacement
- Certification
- NSF/ANSI 42 and/or 53 for the stated claim
Begin with a treatment objective
Describe the actual problem: hardness, a specific contaminant, particles, odor or a microbial concern. Confirm it with suitable evidence. Then compare documented equipment performance at the home’s required flow.
A complete system is more than a tank
Service flow, contact time, pressure loss, backwash water, drain provisions, power and maintenance all matter. A branded media name or large vessel does not establish the capacity of a complete treatment train.
Read the certification claim
NSF/ANSI 42 addresses aesthetic claims, 53 health-effect reduction claims, 44 softeners, 58 reverse osmosis, and 55 UV systems. Certification to a standard does not mean every possible claim within that standard applies. Find the exact model, component combination, rated capacity and reduction claim in the certifier’s directory.
Utility water and well water start differently
A utility customer should identify the supplier, disinfectant and current notices. A private well owner needs property-specific testing and a maintenance plan. Removing a disinfectant can change microbial conditions in downstream plumbing; treatment needs appropriate upkeep.
Sources & further reading
Primary references for this guide. Confirm current requirements and notices with the responsible authority.
General information helps you prepare. Actual conditions, equipment instructions and the responsible authority determine the work at your property.