Water Filters: Sorting Out the Types for Your Home

Photo courtesy of Aquasana.

Many homeowners need a water filtration system, but the systems vary in cost and effectiveness. Here's a look the different types to determine which is right for your home.

"Whole house" water filters located along the main supply line treat all the water throughout your home, making it cleaner, healthier, and free from unwanted tastes and smells. A whole house water filtration system can protect against dangerous bacteria and remove minerals for softer hair and skin. Most whole house systems utilize various types of filters through several stages of filtration. Each filtration stage targets a different contaminant. You'll need to select a filter or whole-house system that targets the unwanted contaminants in your home's water, but there's no need to spend money on a type of filter you do not need.

A smart first step in selecting a system is to check your local water quality report to learn of any specific contaminants you need to address.

Here’s a rundown of the different types water filters offered as stages of filtration, or as add-ons of a whole house system.

Sediment filters Often the first line of defense against unwanted particles, sediment filters are usually included in the pre-filter stage of a whole house system and remove larger granular particles before the water gets filtered for chemicals and other contaminants.

Sediment filters remove dirt, rust, silt, clay, sand and other debris. Removing these particles before filtration also prevents clogging at other stages of filtration, which can extend the life of the system. Pros

• Removes large particles in water

• Fairly easy to install

• Relatively low cost

• Improves performance and longevity of the entire system

Cons

• Replacements needed often

• Does not remove chemicals, bacteria, or viruses

Activated carbon filters Activated carbon is derived from natural materials like charcoal. When water passes through the medium, it absorbs chemicals and releases clean into the water supply. Granular activated carbon (GAC) filters are commonly found in whole house filter systems because the loose carbon particles work efficiently with high water pressure.

Pros

• Improves taste

• Improves smell

• Removes chemicals like chlorine

• Relatively affordable

Cons

• Doesn’t remove large particles like metal

Catalytic carbon filters Catalytic carbon filters add gas processing at high temperatures to the process for activated carbon filtration to remove chloramines.

Pro

• Removes chloramines

Cons

• Doesn’t remove chlorine as well

• Most heavy metals unaffected

• Additional cost

KDF Copper-Zinc filters

Kinetic Degradation Fluxion filters, or KDF filters, use copper and zinc to provide additional support the other components of your home water filtration system. With the materials' natural antimicrobial properties, these filters control the release of microorganisms like algae into your water. A KDF-55 or KDF-85 filter is sometimes the final phase for a whole house water-filtration system.

Pros

• Inhibits bacteria and algae growth

• Improves taste and smell

Cons

• Doesn’t fully remove biomaterials

UV filters UV filters use ultraviolet light to eliminate dangerous microorganisms such as E Coli, giardia, and other bacteria and fungi which can cause illness. These filters are often sold as optional add-ons, but may be necessary for people who rely on private well water.

Pros

• Sterilizes up to 99.99% of bacteria and viruses and 99% of cysts

• Annual lamp replacement is easy

• No chemicals or particles used

Cons

• Must remain connected to a power source

• No removal of particles or chemical contaminants

Softeners and conditioners

Water softeners and conditioners are used in conjunction with whole house water filters to remove magnesium and calcium known to cause "hard water." These minerals can wreak havoc on a home’s plumbing and appliances.

• Softeners: Utilize ion exchange, which requires salt, to swap the hard water mineral ions with ions from the salt. In addition to salt, softeners also require electricity and generate wastewater.

• Salt-Free Conditioners: Utilize a scale control media to attract and neutralize mineral ions by forming small, harmless crystals. Salt-free conditioners are considered better for the environment because they require no electricity and produce no wastewater.

Pros

• Prevents scale buildup by addressing hard water minerals

• Protects pipes and appliances

• Improves water texture

• Improves laundry (less damage after washing)

• Cleaner, streak-free dishes

Cons

• No filtration of chemical contaminants

• Can be expensive

Calcite filters

Calcite filters, AKA acid neutralizers, are used to balance the water’s pH levels using natural minerals.

Pros

• Makes acidic water more basic for improved taste

Cons

• Removes no contaminants, only changes pH level

Reverse Osmosis filters Reverse Osmosis filters are the most expensive type of whole house water filter but are seen as a single solution to most household water problems. Reverse Osmosis filters work by pushing water through a semi-permeable membrane at high pressure, allowing only clean water to pass into the household supply. These filters are commonly considered the most effective filtration method, but in some cases can actually remove healthy minerals, which negatively affect the water's taste. Some systems include a "remineralizer" that restores healthy minerals lost in the RO process. Due to the high cost of a whole house RO system, homeowners might consider an under-sink RO system located at the most commonly used faucet for drinking water.

Pros

• Offers the most powerful form of filtration

• Provides the best water for cooking and drinking

Cons

• Expensive

• Sometimes removes healthy minerals, negatively affecting the water's taste

• Some systems create wastewater
  

As you can see, there are several types of water filters that serve different purposes. Consider the contaminants in your area and choose a system that offers the stages of filtration you’ll need for your home.