While many people understand the need to filter their water to remove potentially harmful contaminants that maybe present, when it comes to choosing between a water purifier vs water filter, they are not aware of the differences between the two options. In this article we will compare the subtle differences between a water filter vs purifier to help you narrow down your selection and choose the best water filtration system for your needs.

At a glance

In a nutshell, the key difference between a water purifier vs water filter lies in the extent of protection each of these water filtration systems offer against pathogenic microoganisms.

Water filter vs purifier: What's the difference?

Water filters are typically capable of removing bacteria and protozoa that may be present in water, but are unable to remove viruses due to their tiny size. The filter media in a water purifier, on the other hand, has a much finer pore size and is able to remove tiny microorganisms that would typically get through the filter media of a water filter. In addition to removing bacteria and protozoa, water purifiers are also capable of removing viruses, rendering your drinking water that much safer to drink. 

Water purifier vs water filter: How do they work?

Typically, water filters do exactly as their name implies. The filter media housed within the water filter strains pollutants out of the water as the water passes through they filter. However, due to their small size, viruses and other tiny pollutants are able to slip through the pores in the filter media and remain in the water even after it is filtered.

Viruses can be killed by treating water with chemicals (e.g. bleach or disinfection tablets), exposing water to ultra violet light, or boiling. However, while these strategies are useful for killing viruses and other microorganisms in a pinch, they are ineffective at removing other harmful contaminants such as heavy metals, pesticides and other chemicals that are often found in drinking water. In fact, chemical disinfection can lead to the formation of chemical byproducts that do more harm than good, and boiling water can actually increase concentrations of pollutants such as heavy metals. These treatment options also do not remove larger particles such as silt and sediment that can make water look unsightly and just plain unpleasant to drink. A gravity fed water purifier, such as the Big Berkey that contains filter media with ultra-fine pores specifically designed to remove viruses, offers the best of both worlds. It will physically strain out all the contaminants that pass through the filter media, from minute viruses to larger sediment and everything inbetween.

A full list of contaminants the Berkey is certified to remove can be found here.

Water purifier vs filter: Which one is best for me?

Since municipal water treatment facilities add disinfection chemicals such as chlorine during the water treatment process to kill pathogenic microoganisms, the risk of exposure to harmful microoganisms is much lower in treated water compared to borehole water or any other source of raw water.

Depending on the contaminants present in the water, a water filter may be adequate for use in situations where tap water is disinfected with chlorine, UV light, or other disinfection process during the water treatment process before it is supplied to the home or end point. A water filter will typically remove a wide range of contaminants, including chlorine and other disinfectant chemicals used in the treatment process, as well as any bacteria and protozoa that may have got into the water after it left the treatment plant. Filtering your water using a water filter will also remove sediment and will improve the overall clarity, taste and smell of your water.

By the same token, if you are backpacking in the outback where the countryside is pristine and water sources are less likely to be polluted by humans, you are less likely to be exposed to harmful viruses. In cases such as these, a water filter may be adequate as it will be able to remove protozoa (such as Giardia and Cryptosporidium) and bacteria (such as E. coli and Salmonella), which can be transferred through both animal and human waste and therefore will still pose a health threat, even in pristine environments. However, its important to note that while back-county water sources are likely to be less polluted than water sources in areas that see more human traffic, this water is by no means treated, and there is still a risk of contamination from natural sources. So choose your water filter wisely. A water filter that is designed primarily to improve the taste and odor of tap water is not likely to offer you the protection you need. You will need a water filter that is capable or removing contaminants down to at least 0.2 microns. If you are in any doubt, rather opt for a water purifier (capable of removing contaminants down to 0.02 microns — note the extra zero, which translates to much smaller contaminants being filtered out) that will give you much greater protection from a wider range of contaminants.

In emergency situations and when traveling to under-developed countries with poor sanitation and water treatment facilities, your safest bet would be a water purifier. Similarly, if your drinking water is sourced from a borehole, spring, lake or other raw water source where the risk of exposure to microorganisms, particularly pathogenic viruses such as Hepatitis A and Norovirus, is much greater, it's best to add that extra level of protection that a water purifier offers.

The bottom line

When it comes to your health, it's best to not take any chances. Especially concerning the quality of your drinking water. Considering that choosing between a water purifier vs water filter can significantly affect the quality and safety of your drinking water, we advise that you err on the side of caution and opt for a good quality water purifier such any of the options in the Berkey range that will remove a far wider range of contaminants to a far greater degree.

Berkey models & upfront cost

Berkey offers a wide variety of water purifiers to choose from, ranging from the compact 1.5 gallon Travel Berkey (the smallest in the Berkey range), right up to the Crown Berkey (which at 6 gallons, is Berkey's largest offering) in stainless steel. Berkey also offers a light-weight BPA-free plastic water purifier (the Berkey Light) with a capacity of 2.75 gallons, which is also slightly cheaper than the stainless steel options, making it an extremely affordable water purifier for those working with a small budget who still want the overall performance of a water purifier.

• Travel Berkey water filter (1.5 gallons) - $285
• Big Berkey water filter (2.25 gallons) - $317
• Royal Berkey water filter(3.25 gallons) - $350
• Imperial Berkey water filter (4.5 gallons) - $385
• Crown Berkey water filter (6 gallons) - $407
• Berkey Light water filter (2.75 gallons) - $261

As we can see, the purchase costs of the Berkey water purifiers range between $261 and $407. The purchase price includes two Black Berkey purification elements , with the option to purchase an additional set to double the lifespan and filtering performance of the system (the Crown Berkey can be upgraded to 4, 6 or 8 purification elements according to user preference). If fluoride and arsenic are contaminants that are of concern to you, you can also add an optional set of arsenic and fluoride filters ($70 per set of 2) to the lower chamber of the system to remove these contaminants.