When looking at different gravity filters, it’s hard to tell which brands and products are best.
Is Berkey, the water filtration giant, truly the best option for your home, or would you be better off going with a newer brand like ZeroWater?
We put the two most popular countertop gravity filters for each brand head-to-head and compared them on criteria like their contaminants removed and filter lifespans to find out which one brings the most to the table.
Table of Contents
Final Summary – ZeroWater vs Berkey Gravity Filters
We chose the Big Berkey for the best gravity filter due to the extremely high number of contaminants removed, faster filtration rate, and longer filter lifespan. While the ZeroWater Dispenser is less expensive up front, we believe the long-term benefits outweigh the higher initial price.
These are the main things we looked at when comparing the two filters, and each category is broken down in further detail below:
|ZeroWater Dispenser||Big Berkey|
|Filtration Rate||49 minutes||36 minutes|
|Filter Lifespan||1-2 years||10 years|
|Storage Capacity||2.5 gallons||2.25 gallons|
ZeroWater vs Berkey Gravity Filters Overview
Before we delve into the nitty-gritty specifications for each filter, here are the main points for each one including the kind of filter they use, their dimensions and storage capacity, and how they work to deliver clean, filtered water.
Type of Filter Used
ZeroWater uses a 5-stage system in their products that use activated carbon, KDF, and ion exchange technology.
Similarly, Berkey uses the Black Berkey filters in their products that contain a proprietary blend of five different filtration media. These filters combine activated carbon and ion exchange with microfiltration.
Dimensions and Storage Capacity
The ZeroWater Dispenser is 11 x 9.8 x 19.8 inches and features a glass freshwater holding tank. When full, the tank has a 40 cup capacity and dispenses water through a spout at the bottom.
The Big Berkey, on the other hand, is 8.5 inches in diameter and 19.25 inches tall and is made out of stainless steel. The tank has a 2.25-gallon capacity or 36 cups, and it also has a spout at the bottom to dispense water. One optional feature for the Big Berkey is a metal stand that you can place it on that will elevate the spout for easier pouring.
How They Work
Both the ZeroWater Dispenser and the Big Berkey use gravity filtration to get the job done, which means the weight of the unfiltered water forces it through the filter.
Both products are also used by filling up the tap water tank at the top and then letting the gravity filtration process work. Fresh, filtered water will then accumulate in the storage tanks at the bottom.
Now let’s look at how each brand does when compared on key specifications like contaminants removed and filtration rate.
The following chart is a summary of the different classes of contaminants, and how many contaminants in each class the two filters remove.
|ZeroWater Dispenser||Big Berkey|
|Semi-Volatile Organic Chemicals||2||52|
|Disinfectants (Including Chlorine and Chloramine)||2||3|
|Inorganic Chemicals (Including Heavy Metals)||23||24|
|Total Dissolved Solids||✓||X|
|Microbial Cyst Reduction||X||✓|
Berkey blows ZeroWater away on paper when it comes to the number of contaminants removed, but ZeroWater may actually perform better than they let on. The activated carbon filtration technology in the ZeroWater filters should work on many of the same organic chemicals as the Black Berkey filters.
However, ZeroWater has only published their filter’s performance for the contaminants that are tested for NSF certification so there’s currently no way to know. You can see the full list of contaminants removed for ZeroWater here, and for Berkey here.
The ZeroWater Dispenser does work on total dissolved solids (TDS) which contribute to water hardness, while the Big Berkey does not. This function won’t replace a true water softener, however, it may be of interest to homeowners with higher than normal amounts of TDS. The easiest way to find out exactly what’s in your water and what filter you need to remove those contaminants is to have it tested.
Filter Lifespan and Durability
The lifespan of a filter can be measured in the number of gallons of water it can filter before going bad, and this number is expressed in gallons. Depending on your household size and water usage, 40 gallons roughly translates to 1-2 months of filter life.
The ZeroWater Dispenser filter will generally last for 25 to 40 gallons depending on the amount of TDS in your water, and the dispenser even comes with a TDS meter so you can monitor it from home. ZeroWater recommends replacing the filter when the TDS reading reaches 006 or higher. There’s also a 90-day warranty on this dispenser to protect against manufacturer defects.
The Black Berkey filters last much longer – each has a capacity of 3,000 gallons. Big Berkey models come with the ability to equip two or four filters, and their lifespans are additive. This means a two-filter system will last for about 10 years, while a four-filter system can last 20+ years. Berkey also has a lifetime warranty on their model.
While neither system has a particularly fast filtration rate, the Big Berkey has the edge. It takes roughly 36 minutes for the filter to fill the entire 36-cup storage tank, but it takes the ZeroWater Dispenser 44 minutes to fill the same amount and about 49 minutes to fill the whole tank.
The one area that ZeroWater trumps Berkey is in their certifications. Water filters can be independently certified by non-profit organizations like the National Sanitation Foundation (NSF) and the Water Quality Association (WQA). These organizations test various products to see how they perform against different industry quality standards. The products are then certified for the standards they perform at.
The ZeroWater Dispenser has been NSF certified for standard 42, which means it improves the taste and odor of water, and for 53 which means it reduces/removes harmful contaminants to below safe levels.
While the Big Berkey has not been certified for any standards, it has been tested by other independent labs and found to perform at the level of multiple standards including 42, 53, and P473, so it seems it’s just a matter of them not wanting to invest in the certification process.
The ZeroWater Dispenser is significantly cheaper than the Big Berkey at only $74.99 for the base price. You can also get a 16-pack of filters for $149.99 which should last you roughly two years, and over five years you’ll spend about $375 in total on the model and filter replacements.
The Big Berkey, on the other hand, goes for $278 to start for the 2-filter model and $388 for the 4-filter model. Having said that, you shouldn’t have to replace your filters for at least 5-10 years so you end up saving more in the long run with this product.
Types of Models Each Company Offers
Berkey and ZeroWater both offer other options for countertop gravity filters, and ZeroWater also has water filter pitchers available. Berkey doesn’t make a pitcher, but they have shower head filters and a water bottle filter to choose from as well.
Customer Reviews and Complaints
The Big Berkey has a 4.7 out of 5 rating. The most common customer complaints are that the stainless steel housing starts to rust over time and that there can be a rubbery taste to the filtered water.
In comparison, the ZeroWater Dispenser has a 4.4 out of 5 rating and the main complaint is of poor quality control for chrome flakes getting into the water from the base.
Pros and Cons
Here are the main advantages and disadvantages of each model:
ZeroWater Dispenser Pros
- Inexpensive up front
- 4.4 out of 5 rating
- NSF certified
- 90-day warranty
- Reduces TDS
- Comes with a TDS meter
- Larger capacity
ZeroWater Dispenser Cons
- Slow filtration rate
- Short filter lifespan
- Not tested for as many contaminants
- Some customers report chrome flakes in the water
Big Berkey Pros
- Large number of contaminants removed
- Long filter lifespans
- 4.7 out of 5 rating
- Lifetime warranty
- Optional stand available
- Saves money over time
Big Berkey Cons
- Slow filtration rate
- Not certified
- Does not reduce TDS
- Some customers report rubbery taste to water and rusting of the housing
Due to the long filter lifespan, the potential to save money over time, the 232 contaminants removed, and the lifetime warranty, we believe that the Big Berkey is the better gravity countertop filter over the ZeroWater 40-Cup Dispenser.