Carbon Water Filters: What They Are & How They Work
Clean, great-tasting water is a priority for many households, and carbon water filters have become one of the most effective and widely used solutions for improving water quality.
They can be found in everything from under sink systems to fridge dispensers and portable filter jugs. They help remove contaminants and improve the taste and smell of drinking water.
Carbon filters offer excellent purification benefits, but they do have limitations. Understanding how they work, what they remove (and don’t), and how to maintain them can help you make the most of your filtration system.
How Do Carbon Water Filters Work?
Carbon water filters remove contaminants through a process called adsorption, where impurities stick to the filter’s surface rather than being absorbed like a sponge.
Made from charred materials like wood or coconut shells, carbon filters are highly porous, with millions of tiny pores that trap unwanted particles as water flows through.
Their large surface area makes them effective at reducing chlorine, foul tastes, and odours commonly left behind by water treatment processes.
The filtration efficiency depends on factors like pore size (measured in microns), water pressure, and flow rate—slower flow allows more contact time, improving the filter’s ability to capture contaminants.
What Do & Don’t Carbon Water Filters Remove from Water?
Carbon water filters effectively remove many common contaminants, but they have limitations. Checking for NSF certification can help determine a filter’s specific capabilities.
Here’s what carbon filters can and cannot remove.
Does Remove:
Does Not Remove:
- Limescale – Does not soften hard water.
- Fluoride – Not removed by standard carbon filters.
- Heavy metals – Only removed if the filter has additional filtration media.
- PFAs – Standard carbon filters may not remove these chemicals.
- Bacteria – If certified
Some specialised carbon blends can improve filtration. For example, silver-infused carbon kills bacteria, while iron-reduction carbon (using KDF media) converts heavy metals into a solid state for removal.
How Long Do Carbon Water Filters Last?
Carbon water filters should be replaced every six months to one year, depending on usage and water quality.
Using a filter beyond its lifespan can be counterproductive—once its pores become saturated with contaminants, trapped particles may start to break free and re-enter your water supply.
At Finerfilters, you can take advantage of our buy & save promotions or subscribe for a hassle-free, regular supply of replacement filters. With a subscription, you’ll never have to worry about missing a replacement.
How Do I Clean Them?
Carbon water filters are not designed to be cleaned and reused. Rinsing may remove surface debris, but it won’t restore the filter’s ability to trap contaminants.
If your filter becomes clogged or the water flow slows down, it’s a sign that it needs to be replaced.
Types of Carbon Filters
Granular-activated carbon filters
GAC filters use loose granules of activated carbon to quickly remove impurities as water flows through. Their open structure allows for a fast flow rate, making them better for high-demand filtration.
Carbon block filters
Carbon block filters offer superior filtration with up to 10 times more surface area than GAC filters. Their dense structure prevents water from bypassing the carbon, ensuring thorough contaminant removal. The trade-off? A slightly slower flow rate.
Radial flow GAC carbon filters
Radial flow filters offer the best of both worlds—the high surface area of carbon block filters combined with the fast flow rate of GAC filters. Water flows in through the side, making full contact with the carbon granules for efficient, high-speed filtration.
Alternatives To Carbon Water Filters
Reverse osmosis (RO) systems provide a more advanced filtration method. While carbon filters are often used as part of the RO process, their role is primarily to protect the system’s membrane from damage caused by chlorine.
Unlike carbon filters, RO systems use a semi-permeable membrane to effectively remove dissolved inorganic compounds, heavy metals, and even radionuclides from water.
This multi-stage filtration process ensures a higher level of purification—making it a great alternative.
Choosing the Right Filter
At Finerfilters, we offer a full range of filters, including carbon water filters, designed to meet both commercial and domestic needs.
Whether you’re looking for a simple solution or a more advanced filtration system, our selection has something for everyone.
For more information on filtration and expert advice, be sure to explore our blog. If you need help choosing the right filter, don’t hesitate to contact our team via the help centre.