How Do Water Filters Work?

Why Water Filtration

If you’re concerned about water quality and shopping for a water filter, you might be overwhelmed by choice. Knowing how do water filters work can often answer any questions about which one best fits your needs.

Why Water Filtration

The EPA sets national standards that municipal water treatment plants have to meet.

However, Florida’s measures to protect precious natural resources and wildlife often impacts water treatment. The state has its own list of variances and alternative criteria. While the public water supply is safe, it often doesn’t taste very nice.

Adding a water filtration system to your home will fresh, clean, pleasant tasting water.

The Process of Water Filtration

Water filters work by both mechanical and chemical processes. However, most use the following methods or a combination of them:

Mechanical filtering

Water filters contain media that is permeable but has lots of surface area. Water must pass through the media, but the openings in it are small enough to trap particulate matter. The surfaces of the filter media capture sediment and other contaminants.

Reverse osmosis filtering

Reverse Osmosis is another type of mechanical filtering. However, it takes advantage of the unique properties of TFC (thin film composite). These water filters force water through a TFC membrane that water can permeate, but many contaminants cannot.

Charcoal processing

Activated charcoal is a long-used method for reducing contaminants in water. Carbon attracts and captures certain elements, such as lead. Charcoal filters have a great deal of internal and external surface area. Because of this, it works like a sponge to trap contaminants by adsorption.

Adsorption is the ability of a solid to trap gas or liquids in a thin film, and the numerous pockets inside a carbon filter make this incredibly efficient.


Sequestration is a type of chemical filtering process that reduces the impact of mineral sediments. In this type of filters, polyphosphates are added to the water. This process doesn’t’ remove particulates, but instead keeps them soluble so they remain dispersed in the water. This prevents mineral buildup in pipes and fixtures.

Ion Exchange

Another chemical process is ion exchange, which also removes mineral particulates from drinking water. These filters channel water through small beads made of an ion exchange resin. Simply put, the beads trap magnesium and calcium ions and exchange them for different ions.

In water softening, the resin exchanges sodium ions for calcium and magnesium ions. In deionization, the beads will swap hydrogen for cations or hydroxyl ions for anions. This process also removes mineral particulates and is often used in reverse osmosis systems to prepare water for the physical filtration process.

Perfectly Pure

Water quality is important to the health of you and your family. It’s also critical to the longevity of your dishwasher, refrigerator, and other appliances that use water.

Make an appointment with the plumbing pros at Benjamin Franklin Plumbing in Port St. Lucie today about installing a water filtration system in your home.