Hard water can quietly wear down a home’s plumbing, appliances, and fixtures. It also leaves chalky spots on dishes, clogs showerheads, shortens the life of water heaters, and makes soap harder to rinse away.
If you’ve noticed these issues, you’ve probably started researching water softeners, where two questions come up again and again:
- How does a water softener work?
- What size water softener do I need?
Let’s dive into both so you can make an informed decision and enjoy a consistent supply of soft water for everyday use.
What Is Hard Water?
Water is considered “hard” if it contains high levels of dissolved magnesium and calcium. While these compounds are not dangerous to drink, they can lead to issues in your plumbing system. This is because they create scale inside pipes.
Scale, also known as limescale, is a chalky white residue that hard water causes to form on surfaces and in appliances. This mineral buildup reduces water flow in pipes, diminishes appliance efficiency, and leaves spots on dishes and fixtures.
Scale also reacts with soap, producing a sticky residue that’s tough to rinse from skin and hair. Addressing hard water in your home will not only make your water more usable, but will also help your equipment run more efficiently and can extend the life of dishwashers, washing machines, and water heaters.
How a Water Softener Works
Ion Exchange
Water softeners operate through the ion exchange process. Here’s an overview of that process:
- Water enters the resin tank. Inside are thousands of small beads of resin charged with potassium or sodium ions.
- Minerals are captured. As hard water passes through, any calcium and magnesium ions it contains “stick” to the beads.
- Soft water flows out. The minerals stay on the resin, while softened water leaves the tank for use everywhere in your home.
This swap happens continuously whenever you use water, preventing hard water from reaching your faucets and appliances.
Inside a Typical Water Softener
A residential softening system usually has three main components:
- Resin (mineral) tank: Where ion exchange occurs.
- Brine tank: Stores a salt or potassium solution used to recharge the resin.
- Control valve: Measures water use and starts regeneration automatically when needed.
Together, they provide a steady supply of soft water without daily attention.
Regeneration: How the System Refreshes Itself
As the resin beads collect hardness minerals, they eventually become saturated. That’s when the softener begins a regeneration cycle:
- Backwash: Flushes sediment from the resin bed.
- Brine draw: A concentrated brine solution flows through the resin, replacing captured calcium and magnesium with sodium or potassium.
- Rinse and refill: The tank is rinsed clean, and the brine tank refills for the next cycle.
Modern metered softeners track how much water you use and regenerate only when necessary, saving salt and water.
What Size Water Softener Do I Need?
To size your softener:
- Measure hardness in grains per gallon (gpg).
- Estimate daily water use: Multiply the number of household members by ~75 gallons.
- Multiply hardness × gallons: This gives your daily “grains of hardness.”
- Match capacity: Select a softener with enough grain capacity to last about a week between regenerations.
Example:
A family of four, using 300 gallons per day with 10 gpg hardness:
300 × 10 = 3,000 grains/day → A 24,000–32,000 grain unit is a good fit.
Note: Oversizing isn’t always better. If a unit regenerates too infrequently, the resin may foul, or water can taste stale. The best choice balances capacity with efficient operation.
How to Test Your Water Hardness
Before you can choose the right softener, you need to know how hard your water is. Options include:
- At-home test strips or kits from hardware stores.
- Digital testers that give a quick reading in grains per gallon (gpg).
- Professional testing through your local plumber or municipal lab.
Most homes have between 5 and 15 gpg, but some well systems or rural supplies can exceed 25 gpg.
Salt, Potassium, and Environmental Considerations
Most softeners use salt (sodium chloride). There are also models that use potassium chloride, which is an alternative for those limiting sodium or concerned about brine discharge. Potassium is more expensive but adds no sodium to drinking water and can be friendlier to landscaping where discharged water is reused.
If you’re on a septic system or live in an area with brine restrictions, your plumber can recommend systems or settings that minimize waste.
Maintaining Your Water Softener
A quality softener is low-maintenance but does need attention. To keep yours running optimally, you should:
- Check salt levels monthly and refill as needed.
- Break up salt bridges (hard crusts) that can form in the brine tank.
- Clean the brine tank occasionally to remove sediment.
- Have a professional service the control valve and resin every few years.
With proper care, resin beds typically last 10–15 years, while control valves can last even longer.
Common Water Softener Questions
Does a water softener change the taste of water?
Softened water may taste slightly different because of added sodium or potassium. However, this subtle difference in taste frequently goes unnoticed. If you happen to dislike the taste of softened water, you can keep a dedicated cold-water tap that does not use softened water.
Can a softener remove iron?
Some water softener models can handle low levels of ferrous iron. However, heavy iron can frequently only be removed by a dedicated filter.
Will soft water harm plants or lawns?
Over time, softened water can harm your soil (and thus your plants and lawn) because of its sodium content. A plumber can help you bypass the outdoor spigots.
How long does installation take?
A professional plumber can usually install a new softener in half a day.
Work With Trusted Professionals
Choosing, sizing, and installing a water softener is easiest with expert guidance. At Arnold & Sons Plumbing, we’ve helped families throughout Peoria and the surrounding area enjoy cleaner, softer water for decades.
Visit our Water Softeners page to explore options or contact us to schedule testing and installation.
