Why Use Activated Carbon Filters?
As an all-natural method to purify water, it’s hardly a surprise that carbon is used in almost every type of water filter system from residential filters to commercial ones.
Activated carbon owes its popularity to its highly porous structure that is capable of adsorbing various chemicals and organic substances that may be contaminating your tap water.
Mixing regular carbon with oxygen “activates” it, opening up tiny pores between carbon atoms — referred to as the “carbon substrate” — which then attract and trap harmful contaminants, transforming water sources into tasty, contaminant-free drinking water.
Carbon filters are used in residential filters as stand-alone filters or as a complementary filter in multi-stage water filter systems.
If you’re unfamiliar with the benefits of activated carbon filters, here are the best reasons why you should buy these filters:
#1 Natural & Sustainable Way To Filter Tap Water
The most common materials serving as a base for activated carbon filters include wood, lignite, bitumen, and coconut shell. Of all these, coconut shell carbon has the highest hardness, highest microporous substrate, and it’s the least dusty, which makes it an ideal choice for a filter media.
Another reason why coconut shell is considered the best base material for activated carbon filters is because it’s a renewable resource, and the harvest of coconut fruits has no negative impact on coconut trees or the environment.
As a sustainable and environmentally friendly filter media, coconut shell carbon is an affordable and renewable filter media that can be found in shower filters, fridge filters, countertop filters, inline filters, undersink filters, and whole house systems.
# 2 Suitable for Targeting a Wide Range of Contaminants
Activated carbon filters are excellent at removing chlorine and THMs (chlorine by-product) from water, which is why they are used in any residential water treatment unit that targets chemical disinfectants and their by-products.
Other contaminants and substances removed or reduced by activated carbon include: volatile organic chemicals, pesticides, herbicides, dirt, fine sediments, rust, sand, limescale, and other contaminants attracted to carbon.
# 3 Versatile Filters That Play Well With Other Filters
There are two types of carbon filters used in water filter systems — carbon block filters and granular activated carbon (GAC) filters. The difference between the two is that while carbon block filters are a solid block of compressed carbon, GAC filters contain loose granules of activated carbon.
Thanks to their uniformity, carbon block filters allow for a longer contact time with water, which leads to a better contaminant removal capacity compared to GAC filters. However, GAC filters outshine carbon block filters in terms of flow rates. This is why GAC filters are predominantly used in shower filters to ensure the least amount of pressure drop.
Both GAC and carbon block filters can be used in combination with other filter media within the same filter cartridge (e.g. GAC filters are often combined with ceramic spheres in shower filters, or carbon block filters are often used as inserts in ceramic filter candles), and even as separate filters in complex water filter systems like multi-stage reverse osmosis water filters, or whole house water filters.
# 4 Best Filters For Improving Taste and Odour Of Water
Carbon filters are the ultimate in improving the taste and odour of tap water by removing any strange aftertastes caused by chlorine, algae blooms or other issues. Both carbon block filters and GAC filters are commonly used as post-filters or polishing filters in reverse osmosis filter systems.
# 5 Carbon Filters are Completely Safe & Don’t Add Anything to Water
Activated carbon filters are a completely safe method to filter tap water. Nothing is added to your water as it passes through the carbon filter bed, so you don’t have to worry about chemicals or unwanted substances leaching into the water.
Unlike reverse osmosis membranes, carbon filters don’t remove healthy minerals from water, allowing you to enjoy contaminant-free water without losing out on the health benefits of naturally occurring minerals in your tap water.
# 6 Water Filters with Carbon Filters Are Affordable & Low-Maintenance
Carbon filters are some of the most affordable filters available and the most popular water filters like Brita pitchers, Big Berkey gravity water filters, or Ecosoft reverse osmosis filters all use carbon as a filter media.
Carbon filters are easy to replace, especially those that use the quick-change filter technology, and don’t have any special maintenance requirements.
Since no filter media is perfect, carbon filters have their shortcomings too. On their own, activated carbon filters are unable to remove certain contaminants, namely those contaminants that are not attracted to carbon, such as fluoride, heavy metals, nitrites, sodium.
Even though some carbon filters can remove certain bacteria like Giardia or Cryptosporidium if the filter has a low micron rating (think sub-micron level filtration like the one offered by the Watts C-Max Coconut Shell Carbon Block Cartridge, which has a 0.5 micron rating), most carbon filters don’t excel at removing viruses or pathogenic bacteria, which is why they must be used in combination with other filters that can target those issues as well.
Compared to other filter media like reverse osmosis membranes or ceramic filters, activated carbon filters tend to have a shorter service life given that the bonding sites in these filters become saturated with contaminants. When this happens, the filters stop working and they need to be replaced to avoid bacterial growth within the filter.
Some carbon filters are infused with trace amounts of silver or zinc, which confer the filters bacteriostatic properties, preventing bacterial growth within the filter, thus, extending their service life.
Final Thoughts On Activated Carbon Filters
Activated carbon can be found in nearly every water filter system either as a pre-filter or a post-filter. Activated carbon filters are usually used as stand-alone filters only in units designed for chlorine removal or tap water taste and odour improvement.
Water filter systems that use activated carbon filters can be a reliable choice if you want to target chlorine and taste or odour issues in your tap water.
Hopefully, our article on the best reasons to buy activated carbon filters has managed to help you understand how these filters work, and the advantages and disadvantages of carbon filters.