Water Filter vs Water Softener: What’s the Difference?


water filtration

First of All, What Is Hard Water?

Hard water is water that contains high levels of dissolved minerals, primarily calcium and magnesium. These minerals can come from a variety of sources, including rock and soil that the water flows over or through, as well as from industrial and agricultural activities. Hard water can cause a variety of problems, including scaling and buildup in plumbing and appliances, decreased soap and detergent efficiency, and dry, itchy skin. Hard water can also leave mineral deposits on dishes and clothing, making them appear cloudy or spotted. In some cases, hard water can also have a metallic taste. The hardness of water is measured in grains per gallon (GPG) or milligrams per liter (mg/L) and it is considered hard when it exceeds 7 GPG or 180 mg/L.

Water Filter vs Water Softener: What’s the Difference

Water filtration and water softening are two different processes that serve distinct purposes. A water filter is a device that removes impurities from the water, such as bacteria, sediment, and chemicals. A water softener, on the other hand, is a device that removes hard water minerals, such as calcium and magnesium, which can cause scaling and buildup in plumbing and appliances.

When it comes to a water filter vs water softener, it’s important to remember that a water softener is technically under the category of a whole house water filtration system. The term 'water filter' encompasses a much larger scope of products which includes more than just water softeners. Examples of other whole house filters include backwashing carbon filters, iron & sulfur removal filters, sediment filters and fluoride adsorption filters just to name a few. These are completely different systems that perform vitally different water purification functions entirely.

While a water softener can help to improve the quality of your water, it may be a good idea to install both a water filter and a water softener to ensure that your water is free of both hard water minerals and impurities.

What Exactly Do Water Filters Do?

Whole house water filters use a wide variety of water purification technologies to treat water contamination. Water filters come in many different types, including carbon filters, reverse osmosis filters, and sediment filters. Advanced media beds are used to remove pollutants from the water through the process of adsorption, ion-exchange, micron-filtration, catalytic conversion and oxidation. There are many types of media and their versatility allows them to treat everything from natural and man-made chemicals to heavy metals. Most work by first trapping or converting contaminants within their matrix and then removing them through the processes of regular backwashing cleaning cycles or media and cartridge replacements.

Carbon filters, also known as activated carbon filters, use a process called adsorption to remove impurities from the water. This process works by trapping the impurities in the carbon, which acts as a sort of "sponge" for the contaminants. Carbon filters are commonly used to remove chlorine, pesticides, and volatile organic compounds (VOCs) from the water.

Reverse osmosis filters use a semi-permeable membrane to filter out impurities. This membrane is incredibly small, allowing only water molecules to pass through. Reverse osmosis filters are commonly used to remove dissolved salts, heavy metals, and other dissolved solids from the water.

Sediment filters are designed to remove large particles, such as sand, silt, and sediment, from the water. These filters are typically made from materials such as polypropylene or cellulose, and they work by trapping the particles in the filter media. Sediment filters are commonly used to remove sediment from well water.

UV lamps are used for microbial concerns, to sterilize water by attacking the DNA of microbial contaminants with ultraviolet light which effectively destroys bacteria, viruses and cysts. Screen, sieve and membrane filtration can also be used to remove pollutants within a wide range of micron ratings.

What Do Water Softeners Do?

Water softeners treat hard water by using salt and ion-exchange resins to remove calcium and magnesium hardness from the water, which can cause scaling and buildup in plumbing and appliances. The most common method used by water softeners is ion exchange. This process works by replacing the hard water minerals with soft water minerals, such as sodium or potassium. Water softeners typically use resin beads that are coated with the softening agent, most commonly a sodium solution. When the hard water passes through the resin bead, the calcium and magnesium ions are attracted to the resin bead, and the sodium ions are released into the water.

There are several benefits to using a water softener such as preventing costly damage to pipes and appliances, improving skin and hair health, as well as reducing the dingy buildup on clothes, dishes, and other household objects exposed to water. Soft water ultimately leaves things feeling and looking a lot cleaner, reducing the need for large amounts of soaps and detergents which can aid both your wallet, and the planet.

Salt Free Water Softener Alternatives

What is the downside to a water softener? For many people, it is the sodium levels. Salt-free water softener alternatives are available for those that don’t want to add salt or chemicals to their water. Salt-free water softeners are an alternative to traditional water softeners that use ion exchange. These salt-less systems use an advanced ceramic media that effectively attracts and neutralizes hard water scaling properties without the need for regeneration, backwashing, or electricity. This process is sometimes referred to as template-assisted crystallization (TAC), which works by causing the hard water minerals to clump together, preventing them from bonding to pipes and appliances. Salt-free water softeners are often called "water conditioners" because they do not actually remove the hard water minerals, they just prevent them from causing problems.

There are some great benefits that come with salt free water softeners. They are typically more eco-friendly because they do not require rinse water and electricity, are easier to maintain, and are 100% salt free making them a more natural and healthy water softening alternative. These salt-free systems are essentially maintenance free and contain no added sodium for your diet.

Do I Need a Water Filter If I Have a Water Softener?

Do water softeners filter water? Does a water filter soften water? The two are not entirely interchangeable even though both are used to improve water quality in the home. Filtered water doesn’t necessarily mean softened water, and vice versa. When it comes to choosing between a water filter vs water softener, while a water softener can help to remove hard water minerals and prevent scaling and buildup, it does not remove impurities such as bacteria and sediment. A water filter is a separate device that is designed to remove these impurities. If you are concerned about the quality of your water, it may be a good idea to install both a water filter and a water softener. This will ensure that your water is free of both hard water minerals and impurities, providing you with the best possible water quality.

Which System Is Right For Your Water Purification Needs?

Water softeners are excellent water purification systems that will protect your home from the harmful effects of hard water scale buildup. However, if you have other water problems such as with water chlorination, bacterial contamination or iron staining, you will need to consider getting a whole house filter system that will treat those specific water concerns as well.

It is quite common for homeowners to install both a water softener and whole house filter to properly treat their incoming water, and these total solution type setups offer more complete filtration coverage. Today’s whole house filters are highly efficient, long lasting and very affordable, making them a great home improvement investment that will protect your health and home for many years to come. Below is a table that lists some common water problems and the systems which can treat them.

View all APEC Whole House Water Systems


Water Problems Health Effects Contaminants Treated Treatment Benefits Recommended
Chlorine, Chemical Odors, Rotten Egg Smell Dry flaky skin, weak brittle hair, asthma, allergies, eczema. Contact w/ carcinogens Chlorine, Chloramines, Hydrogen Sulfide, Pesticides, VOCs, THMs Softer skin & hair, healthier lungs; spa quality water for baths General Whole House Filtration System
Mild Scale Buildup & Hard Water Mineral Deposits N/A Calcium Carbonate, Magnesium, Limescale Salt-free healthy soft water; reduced scale, eco-friendly, maintenance-free, zero wasted water Salt-Free Water Softeners
Heavy Scale Buildup & Hard Water Concerns High blood pressure & heart health concerns from salt added to treat scale Calcium Carbonate, Magnesium, Limescale Salt softened water uses less soaps, improves laundry & removes scale to protect pipes & appliances Salt-Based Water Softeners
Bacteria, Viruses & Microbes Gastrointestinal illnesses, abdominal pain, fever,  infections E.coli, Giardia, Cysts,  Coliform Bacteria, Cryptosporidium Better health with less gas, cramps, diarrhea & illness UV Light Sterilizers
Iron Red Stains, Rust Particles, Rotten Egg Odors N/A Iron, Hydrogen Sulfide, Manganese No more red iron stains on sinks, tubs & toilets; clean & odor-free Iron & Hydrogen Sulfide Removal System
Fluoridation in Public & Natural Water Supplies Dental fluorosis, neurotoxicity & cancer risk Fluoride Protection from toxic fluoride ingestion,  absorption & inhalation Fluoride Removal System
Sediment & Turbidity causing Cloudy, Impure Water Gastrointestinal diseases Fine Particles, Sand, Silt, Clay, Rust, Sediment Clean, clear sparkling water at every faucet Sediment & Turbidity Removal System
Whole House Water Solution

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