Home Water Guides: Softeners, Filters, Water Heaters and Sump Pumps
Test your water before you buy anything. Hardness in grains per gallon sizes a softener, iron and sulfur call for a different filter than chlorine taste, and well water needs a lab test for bacteria and nitrates.
These guides match treatment to the problem, cover flow rate and cartridge costs, plus tankless and heat pump water heaters, heat tape for freezing pipes and sump pump battery backups.
11 home water guides
Best Reverse Osmosis System and What Each Gallon Costs
Reverse osmosis systems ranked by filter cost per gallon, waste water, flow and install: tankless, tank and no-install countertop picks.
Top picks: Waterdrop G2 Tankless Reverse Osmosis System (400 GPD), Waterdrop M6SL Countertop Mineral RO System (no install), Waterdrop G3P600 Tankless Reverse Osmosis System (600 GPD)
Updated Oct 13, 2026
Under Sink Water Filter vs Reverse Osmosis: Which Do You Need?
A carbon under-sink filter costs about 4 cents a gallon and fixes taste. RO costs about 10 cents and removes dissolved solids. Which you need.
Top picks: Waterdrop 10UA Under Sink Filter (direct connect), Waterdrop G2 Tankless Reverse Osmosis System (400 GPD), Waterdrop M6SL Countertop Mineral RO System (no install)
Updated Oct 13, 2026
Best Water Softener for Well Water With Iron, and When a Filter Goes First
How much iron a softener alone can handle, when an iron filter must go first, and the SpringWell, US Water Systems, Aquasure and Fleck picks for wells.
Top picks: SpringWell WS1 Well Water Iron Filter, Aquasure Harmony Series 48,000 Grain Softener, US Water Systems Matrixx inFusion Iron and Sulfur Filter (15 GPM)
Updated Oct 13, 2026
Best Water Softener for a Family of 4: Why 48K Is Usually the Right Size
Sizing math for four people at 10, 15 and 20 gpg, then the 32K to 64K softeners worth buying: Matrixx 48K, Fleck 5600SXT, SpringWell SS1 and SS4, Whirlpool.
Top picks: US Water Systems Matrixx Smart Metered Softener 48K (1.5 cu ft), AFWFilters Fleck 5600SXT 48,000 Grain Softener (10% crosslink resin), Whirlpool WHES40E 40,000 Grain Softener
Updated Oct 13, 2026
Best Whole House Water Softener for 2026, Sized by the Math
The whole house softeners worth buying in 2026, from a budget cabinet to a 64K two-tank. Sizing formula, salt vs salt-free, 10-year cost and DIY install.
Top picks: US Water Systems Matrixx Smart Metered Softener 48K (1.5 cu ft), AFWFilters Fleck 5600SXT 48,000 Grain Softener (10% crosslink resin), US Water Systems Matrixx Smart Metered Softener 64K (2.0 cu ft)
Updated Oct 13, 2026
Best Water Filter for Well Water: Test First, Then Buy
Match the well water filter to your test: sediment, iron, sulfur smell, manganese, bacteria and hardness, with the SpringWell, Matrixx and softener picks.
Top picks: SpringWell WS1 Well Water Iron Filter, US Water Systems Matrixx inFusion Iron and Sulfur Filter (15 GPM), Tap Score Advanced Home Water Test Kit (Well or City)
Updated Oct 13, 2026
Best Tankless Water Heater by Fuel, Flow and Home Size
Gas, propane and electric tankless water heaters matched by GPM, temperature rise and breaker size, plus a heat pump tank for the lowest electric running cost.
Top picks: Rinnai RX199iN condensing gas tankless water heater, Rheem RTG 7.0 GPM indoor natural gas tankless water heater, EcoSmart ECOS 27 electric tankless water heater
Updated Oct 13, 2026
Best Whole House Water Filter for City or Well Water, Sized by Flow
Whole house water filters matched to chlorine, chloramine or well water, sized by GPM and port size, with 10 vs 20 inch cartridges and cartridge cost per year.
Top picks: Waterdrop WHF21-PBH 2-Stage Whole House Filter (10 in.), iSpring WGB22B 2-Stage Whole House Filter (20 in.), iSpring WGB32B-KSNC Chloramine and Heavy Metals Whole House Filter (20 in.)
Updated Oct 28, 2026
Best Heat Pump Water Heater: Tank Size, Yearly Savings and Fit
Heat pump water heaters sized by household, with yearly savings over electric, gas and propane at state rates, space and 240V fit, and rebates after 25C.
Top picks: Senville 50-gallon hybrid heat pump water heater, Rinnai REHP65 65-gallon heat pump water heater, Rinnai REHP80 80-gallon heat pump water heater
Updated Oct 28, 2026
Best Sump Pump Battery Backup Systems for Power Outages
Battery backup sump pumps from Basement Watchdog and Wayne, ranked by gallons an hour at 10 ft of lift, pit fit and alarms, as add-ons or primary-backup combos.
Top picks: Basement Watchdog Special CONNECT battery backup sump pump, Basement Watchdog CITS-50 primary and backup sump pump combo, Wayne WSS30VN primary and backup sump pump combo
Updated Oct 13, 2026
Best Heat Tape for Pipes: Length, Watts per Foot and Cost to Run
Pipe heat cable by length and watts per foot, built-in thermostats, self-regulating vs constant wattage, and what it costs to run all winter.
Top picks: HEATIT 30 ft Self-Regulating Pipe Heat Cable, 3 W/ft, Frost King HC6A Automatic Pipe Heat Cable, 6 ft, VEVOR Self-Regulating Pipe Heating Cable, 30 ft, 5 W/ft
Updated Nov 1, 2026