Water Treatment Buying Checklist Printable Updated March 2, 2026 Use This ChecklistPrint this checklist before shopping for Water Treatment. It covers everything from choosing the right type to avoiding common mistakes. Print This Checklist Research PhaseResearch the 4 types of water treatment availableBest Pitcher: Brita Longlast+ ($30-$40)Best Faucet-Mount: PUR PFM400H ($25-$35)Best Under-Sink: APEC WFS-1000 ($100-$150)Best Overall: Fleck 5600SXT (Salt-Based, 48,000 Grain)Best Premium: SpringWell SS (Salt-Based, 48,000-80,000 Grain)Best Salt-Free: SpringWell FutureSoft (Conditioner)Compare prices across at least 3 brandsRead warranty terms before purchasingCheck compatibility with your existing plumbing Shopping TipsTest your water before buying. A $30-$50 home test kit (Tap Score, National Testing Labs) tells you exactly what contaminants are present. Buy the filter that addresses those specific issues.NSF certification matters. Look for NSF/ANSI 42 (taste and odor), NSF/ANSI 53 (health contaminants like lead), and NSF/ANSI 58 (reverse osmosis). Uncertified filters may claim removal without independent verification.Reverse osmosis removes beneficial minerals along with contaminants. If you want to add minerals back, an RO remineralization filter ($15-$25) adds calcium and magnesium to the filtered water.Test your water hardness before buying. A $5-$10 test strip tells you the GPG. Multiply by daily gallons used (75/person/day) to determine the capacity you need. A 48,000-grain unit covers most households of 2-5 people.Demand-initiated regeneration (metered) saves 30-40% salt compared to timer-based regeneration. Every softener on this list uses metered regeneration. Avoid timer-based units that regenerate on a fixed schedule regardless of usage.Salt cost: a family of four uses 1-2 bags of salt per month ($5-$8 per 40-lb bag). Annual salt cost: $60-$200 depending on hardness and usage. This is the ongoing operating cost of a salt-based softener.Start with a water test. Buy filtration for contaminants actually in YOUR water.Sediment + carbon is the standard two-stage setup for most issues.RO is overkill if your only concern is chlorine taste.Always test your water before buying any filtration. A $30-$50 home test kit (Tap Score, SimpleLab) identifies the specific contaminants present. This prevents buying a $400 RO system when a $50 carbon filter solves your actual problem.Carbon pre-filters are required before RO membranes on municipal water. Chlorine destroys RO membranes. The carbon filter removes chlorine first, then the RO membrane handles everything else.UV systems require clear water to work effectively. Sediment, turbidity, and color in the water block UV light from reaching microorganisms. Always install a sediment pre-filter before UV.Test your hardness before deciding. Below 7 GPG: you probably do not need either. 7-15 GPG: salt-free may be sufficient. Above 15 GPG: salt-based is significantly more effective.If you choose salt-based and are concerned about sodium in drinking water, install an RO filter at the kitchen sink. The RO removes the added sodium from your drinking and cooking water while the rest of the house benefits from soft water.The 'slippery' feel of soft water is not soap residue -- it is your skin's natural oils, which hard water strips away. Soft water leaves your natural oils intact. Many people prefer the feel once they adjust to it.Request your CCR from your utility or find it at epa.gov/ccr.Pay attention to lead if you have a pre-1986 home.If water tastes like chlorine, a whole-house carbon filter eliminates it.Test your water hardness first. Under 7 GPG may not need treatment at all.Salt-based is the only option that truly softens water.If on sodium-restricted diet, use potassium chloride instead of sodium chloride in a salt-based system.Chlorine concern: whole-house carbon is most impactful single upgrade.Lead or fluoride: point-of-use RO at kitchen sink is sufficient.Whole-house + RO is the gold standard for comprehensive treatment. Mistakes to AvoidBuying a whole-house filter thinking it removes everything. Whole-house carbon filters remove chlorine, sediment, and some chemicals. They do not remove TDS, bacteria, fluoride, or heavy metals at the same level as RO.Choosing a filter based on marketing claims without checking NSF certification. 'Removes 99% of contaminants' without NSF testing data is meaningless.Buying an RO system when your only issue is chlorine taste. RO wastes 3 gallons per 1 gallon filtered. A $15 pitcher or $100 carbon filter removes chlorine with zero waste.Buying a salt-free conditioner expecting it to work like a salt-based softener. Salt-free systems reduce scale but do not eliminate hardness. Your water test will still read hard. For heavy scale problems, salt-based is the real solution.Undersizing the softener. A 32,000-grain unit for a family of five with 20 GPG hardness regenerates every 2-3 days, wasting salt and water. Size for 7-10 day regeneration cycles.Buying the cheapest unit and ignoring the control valve quality. The control valve (Fleck, Clack, Autotrol) is the brain of the softener. Cheap off-brand valves fail in 3-5 years. Quality valves last 15-20 years.Buying RO when simple carbon would address the issue.Skipping sediment pre-filter -- particles clog downstream filters.Expecting carbon to remove lead or fluoride -- you need RO.Buying a carbon filter expecting it to remove lead, arsenic, or fluoride. Standard carbon does not remove dissolved metals or minerals. You need RO for those.Installing UV without a pre-filter. Turbid water shields bacteria from the UV light, reducing kill rate below safe levels.Choosing RO for the whole house. Residential RO systems waste 3-4 gallons per 1 gallon filtered. A whole-house RO system wastes thousands of gallons per month. Use RO at the point of use (kitchen sink) and carbon for the rest of the house.Buying a salt-free conditioner expecting it to produce measurably soft water. A hardness test after a salt-free system still reads the same GPG. The minerals are conditioned, not removed.Choosing salt-free for very hard water (above 20 GPG) where salt-based is significantly more effective at preventing scale and improving soap performance.Choosing salt-based without considering the ongoing salt cost and maintenance. A family of four uses $60-$200/year in salt and needs to refill the brine tank monthly.Assuming city water needs no treatment.Ignoring the CCR because water looks and tastes fine.Testing well water once and assuming it stays the same.Expecting salt-free to deliver the same results as salt-based. It conditions, not softens.Installing salt-free on very hard water (15+ GPG). The conditioning effect is minimal at high hardness.Choosing salt-based without a drain connection for regeneration discharge.Only point-of-use when sediment is damaging water heater and appliances.Whole-house RO -- expensive, wasteful, unnecessary for showers and toilets.Assuming fridge filter replaces proper treatment. Installation PrepHave ready: RO system kit (includes filters, membrane, tank, faucet, tubing)Have ready: Adjustable wrenchHave ready: Drill with 1/2-inch bit (if drilling a faucet hole)Assess difficulty level: IntermediateBudget for installation: $150-$400 for system / install is DIYHave ready: UV disinfection unitHave ready: Sediment pre-filter (5 micron)Have ready: Pipe cutter and fittingsAssess difficulty level: IntermediateBudget for installation: $150-$500 for system / install DIY Helpful ResourcesComplete Water Treatment GuideEverything in one placeWater Treatment TypesCompare all typesCost GuidesBudget planning See AlsoReverse Osmosis SystemsBest Water Filters (2025)Under-Sink RO System InstallationAnnual Water Treatment Operating CostsHow to Install a Reverse Osmosis System
