Filter and reverse osmosis tank of a water filtration system.

Comparing Water Filter Technology

Most people researching water filtration technologies are looking for information to help choose the best system for their home.

Depending on the type of water filter you’re interested in, you may be able to choose from a range of different water filter technologies including mechanical, activated carbon, reverse osmosis, ion exchange, and ultraviolet light filtration. With so many options to choose from, it’s important to understand these filter technologies to determine which option is best suited for your needs. To assist you with the buying process, we’ll explain how each of them work.

Mechanical Filtration

Mechanical filtration involves the use of a physical barrier that prevents particles from passing through. As water passes through a mesh filter, particles are suspended and trapped during the process. Mechanical filtration is the most basic form of filtration, as it only filters physical particles like sediment and waste material. As a result, most water filters use mechanical filtration as one of several stages rather than as an independent solution.

Activated Carbon

Activated carbon is one of the most common filtration technologies, which are the primary technology in most pitcher and dispenser filters. Activated carbon filters use a media made from activated charcoal, which is created from materials with high carbon content like wood, coal, and coconut shells. The activated carbon is highly porous, so as water passes through the filter — contaminants stick to the media and impurities are removed. While activated carbon is a step above mechanical filtration, they will not remove contaminants like viruses, bacteria, hard water minerals, and nitrate among others so the technology should be used in conjunction with other methods for adequate contaminant removal. 

Reverse Osmosis (RO) Filtration

Initially developed to turn salt water into potable drinking water, reverse osmosis technology has grown in prevalence in recent years. Reverse osmosis (RO) technology uses the water pressure in your pipes to force water through an RO membrane with an extremely small pore size – so contaminants are left behind and filtered water passes through and is available for use.

Reverse osmosis is generally considered to be the most effective filtration technology. In fact, it’s so effective that the process can strip minerals from water which reduces its health benefits and affects its taste. If you’re considering an RO filter, look for a system with remineralization technology that restores minerals lost during the filtration process. Additionally, you should know that RO systems waste water so if this is important, then you may want to consider other filter technologies.

Ion Exchange

Ion exchange is a filtration technology commonly used in water softeners to address hard water, which is water that has a high concentration of minerals. During ion exchange, water passes through a media (usually a bed of beads) and calcium and magnesium ions that cause hard water are replaced with harmless sodium ions. Ion exchange is not intended as a standalone filtration solution, as it does not remove organic materias and bacteria which means you’ll need to use it in conjunction with another filtration technology.

Template Assisted Crystalization (TAC) 

Template assisted crystalization is a water filtration technology used by water conditioners to treat hard water without salt. Water conditioners that use TAC contain a media that attracts mineral ions commonly found in hard water, and the process addresses the issue by chemically changing the structure of those ions to form small, harmless crystals. So ion exchange removes hard water minerals, while template assisted cystalization alters their chemical composition to make them harmless. Both filtration technologies are intended to address hard water, but neither is suitable as a standalone filtration solution.

Ultraviolet Light (UV)

Ultraviolet light filtration involves the use of UV light to kill viruses and bacteria. When living viruses and bacteria are exposed to UV light, they are inactivated and unable to reproduce. However, this filtration method is only useful for getting rid of viruses and bacteria, it will not remove chemical or physical contaminants. To ensure the water in your home is safe to use, you should invest in another filtration method that will address these concerns and consider UV as an add-on.