Best Gravity Water Filter in 2025? We (Lab-)Tested 7 Systems!

Why did we not test our 7 gravity filters on a non-potable water source? Because we don’t recommend any filtration method to remove disease-causing germs from water since the consequences could be dire if they were not 100% effective. According to the CDC, EPA, and WHO, the best method is to boil your water and if you can’t boil then chemical disinfectants like iodine or chlorine bleach are the next best option. Of course, once your water is disinfected, you could still run it through a gravity filter to remove contaminants like heavy metals.

Gravity Water Filters

• Big Berkey
• Purewell
• ProOne Traveler+ (With Old G2.0 5″ Filter)
• Santevia Gravity Water System

Please note: This page is still a work in progress. Additional content and details will be added shortly – stay tuned!

Paraphrased Video Script

Introduction

Hello everyone and welcome to our big comparison of the most popular gravity water filters that you can use at home and some even outdoors! We’ve thoroughly tested 7 systems, including the Big Berkey – oh boy! – sending filtered water samples to a professional lab in order to check for real-life contaminant reduction. And today, I’m gonna share all the results with you among other things, so you don’t wanna miss this…

The 7 Gravity Filters

• Probably our most popular model but also the one that has caused the most controversy: The Big Berkey. In this video, we’ll try to find out if any of that controversy is well deserved or not.
• Next we have the British Berkefeld by Doulton. Doulton is the company that invented the first gravity water filter using a ceramic filter cartridge.
• Speaking of ceramic filters, we have 2 more: The Alexapure Pro and the ProOne Traveler+.
• Followed by the Waterdrop King.
• And the Purewell which is among the most popular gravity “slash” countertop water filters on Amazon right now.
• And finally, the Santevia Gravity Water System with the Fluoride Removal Filter which we wanted to include due to its remineralization feature.

Side Notes

• Some systems come in different sizes so for comparability we used the 2.25-gallon version for each model, with the Santevia being the exception which is rated at 2.6 gallons storage capacity.
• To avoid counterfeits we made sure to purchase directly from each brand/company or from authorized dealers.
• For the British Berkefeld, we used the Ultra Sterasyl filters.
• For the ProOne Traveler+ we used the 0.5” filter candle.
• For all other systems we used their standard filter elements.
• For the Berkey, Purewell, and Waterdrop we also added the optional fluoride filters.

Testing Procedure

Most importantly, we took a filtered water sample from each of our 7 gravity filters and sent it to a professional and independent third-party lab for analysis. Based on the contaminant levels in our raw tap water, we could then calculate each individual reduction rate to see how each filter performed under real-life conditions.

But before we could do that, we had to setup each system which we did precisely according to instructions including filter priming. Aside from priming, we didn’t process a single gallon of water, so the filters were brand new when we tested them.

For the actual sampling, we filled a single large bucket with raw tap water. We then stirred the water in an attempt to distribute impurities as evenly as possible. We filled the same amount of water into each system with enough water remaining in the bucket at the end to make sure that the last 1 or 2 systems wouldn’t get a higher contaminant load. We waited for the water to filter through. And took the filtered samples directly and without using any containers in between. We also took the unfiltered water sample directly from the bucket. We then shipped all sampling kits on the same day.

Other Tests

• Taste and odor: We couldn’t detect any bad taste or odor in any of the samples. The Santevia water had a pleasant mineral taste to it.
• Speed test: We added 2 gallons of tap water into each system and measured how long it would take to dispense 4 cups or 32 ounces of filtered water.
  • At 11.5 minutes, the Waterdrop King was fastest.
  • Next came the Berkey at just over 40 minutes.
  • The Purewell was third at around 1 hour.
  • All others required around 2 hours or more for 4 cups.
  • ProOne and Alexapure would have been faster with 2 elements in parallel, but only 1 is included in the package.

Other Evaluation Factors

• Initial price tag and annual filter replacement cost
• Usability
• Filter media and filtration process
• Additional pros like all-metal vs plastic faucet, and cons like delayed shipping, bad warranty terms, and user complaints
• Official NSF certifications, NSF testing, and other test data

Lab Results & Recommendations

Before we get into our lab results and product recommendations – it’s important to remember that with this kind of lab testing we can only test for the reduction of contaminants that are actually present in our water supply. Also, such before vs after comparison of contaminant levels is not an exact science and you won’t get 100% accurate results.

Top Performer: Big Berkey

Great! With that out of the way, what’s our top gravity filter recommendation based on the best overall filtration performance? It’s the Big Berkey. Now we know there’s been some controversy surrounding Berkey filters in recent years, and we’ll try to cover all of this in a bit, but FACT IS the Big Berkey came out on top in our lab testing, and it performed really well!

We saw 100% reduction of almost all detected contaminants: Chlorine, all 4 disinfection byproducts (bromodichloromethane, bromoform, dibromochloromethane, and chloroform), copper, barium, boron, lithium, and uranium.
Where we didn’t see a 100% reduction:

• Strontium at 98% (highest rate out of all 7 systems)
• Nitrate at 8% (weak, but Berkey doesn’t claim nitrate reduction)
• Fluoride at 67% (second-best result, ProOne slightly ahead)

Aluminum Leaching Issue

One contaminant stood out: aluminum. There wasn’t any aluminum detected in the raw tap water, whereas the filtered Berkey sample read 1.01 mg/L. This leads us to the first Berkey controversy.

Berkey uses PF-2 fluoride filter cartridges which are based on activated alumina (AA), essentially aluminum oxide. According to Berkey, AA traces leached out of the cartridges and showed up as aluminum in the lab report. Berkey says this is nothing to worry about since AA in drinking water is safe.

Is Activated Alumina Safe?

• AA is also used in dental applications, knee prostheses, and hip replacements.
• Material safety data sheets classify it as non-hazardous and non-bioaccumulative.
• But many sheets state “no information available” for long-term exposure or reproductive toxicity.
• A German government-funded site advised against long-term oral intake of aluminum oxide, noting elevated aluminum in blood could cause side effects.
• The European Food Safety Authority (EFSA) says activated alumina is safe for fluoride removal as long as no aluminum leaches into water above 0.2 mg/L. Our lab found 1.01 mg/L.

Bottom line: even if it’s only AA, I wouldn’t use Berkey’s PF-2 fluoride filters right now. If fluoride removal is your top priority, use a reverse osmosis system instead. If not, skip the PF-2 filters and the Big Berkey is highly effective.

Taste & Speed

• Filtered water tasted and smelled clean.
• Filtration speed: 4 cups in ~40 minutes. Only the Waterdrop King was faster (11 minutes).

Setup & Usability

Assembling and priming the Big Berkey was simple:

1. Use the priming button (rubber washer) under the faucet spout to flush the Black Berkey filters. PF-2 filters flushed upside down as well.
2. Screw in the Black Berkey filters, attach PF-2 filters on the underside.
3. Plug unused holes with the included plugs.
4. Place the top tank on the bottom tank, fill with water, let it filter, empty once, then refill. Ready to use.

Everyday use is straightforward: fill the top tank, wait for filtration, pour from the spigot.
Portability is high — stainless steel tanks are sturdy, and the top fits into the bottom for transport. The Berkey comes in 7 sizes (0.25 to 6 gallons) and supports multiple filter elements in parallel for faster flow.

Build Quality & Price

• Black Berkey filters are Made in the USA.
• Tanks are 304 stainless steel, corrosion resistant.
• Most expensive gravity filter upfront at $367 (2 filters included).
• Free lifetime warranty on system, 2 years on Black filters.
• 5% discount code available from bigberkeywaterfilters.com.

Filter Lifespan Controversy

Berkey claims each Black Berkey filter lasts 3,000 gallons. The problem: lab data often tested for only 25–200 gallons depending on the contaminant. Huge gap between claim and test data.

Other brands do the same (ProOne, Alexapure, Purewell). The exception: British Berkefeld, which aligns claims with test data and has NSF certifications (though only for particulate, cyst, and turbidity).

Despite this, the Big Berkey still outperformed the British Berkefeld in our lab testing. Our recommendation: replace Black filters much sooner, around every 500 gallons per cartridge (~$185 yearly), to stay safe.

Other Concerns About Berkey

1. California ban: Berkey doesn’t sell in CA due to state certification requirements (NSF 61/372). No lead leaching was detected in our testing.
2. Lawsuit: Claims Berkey filters underperform. Berkey says counterfeit filters were likely used. We only buy from authorized dealers.
3. EPA pesticide issue: EPA wanted Berkey to register filters as pesticides because they use silver. Berkey argues silver only protects the filter itself. Our Berkey didn’t leach silver.

So while there’s controversy, our lab results show the Big Berkey performed best overall.

Alternative Pick: Purewell

We recommend the Purewell if your #1 priority is to remove nitrate and you don’t want to use a countertop RO system. In our lab testing, the Purewell achieved 100% nitrate reduction.

Where the Purewell fell short compared to the Berkey:

• Barium reduction: 75%
• Lithium reduction: 0%
• Strontium reduction: 61%
• Fluoride filters didn’t seem to work at all
• Elevated aluminum/AA levels detected in filtered water (so skip fluoride filters)

Other notes:

• #1 budget pick at ~$160 on Amazon
• Annual replacement cost ~$140
• Comes with a tank stand for easier glass filling and a water level window
• 3 tank sizes available
• Filtered water taste and odor good, though some users reported taste issues
• Filtration speed: relatively fast
• Includes all-metal spigot and handle

Cons:

• Almost no independent test data available
• Replace filters sooner than the recommended 3,000 gallons (500 gallons is safer)
• Company website doesn’t inspire much trust
• No clear warranty info
• User complaints: clogged filters and leaking

Outdoor & Emergency Use

We didn’t test for pathogens like bacteria and viruses. If you need a gravity filter for outdoor or emergency use:

• British Berkefeld – the only system NSF-certified for cyst and turbidity reduction. Also tested for bacteria removal.
• Berkey – has older test data for cyst, bacteria, and viruses.

But the safest method is still boiling water, as recommended by the CDC, EPA, and WHO. If boiling isn’t possible, disinfect with chlorine bleach or iodine. You can then filter afterwards for non-volatile contaminants.

Final Recommendations

• Big Berkey – Best overall filtration, despite controversies. Avoid PF-2 filters if fluoride removal is your goal. Replace Black filters sooner (500 gallons per cartridge).
• Purewell – Best budget pick and #1 for nitrate removal. Skip their fluoride filters.
• British Berkefeld – Best choice if cyst/turbidity reduction or pathogen concerns are your top priority.

Wrap-Up

Remember, you can check our full analysis of all 7 gravity water filters including lab reports in our Google Sheet. The sheet and the description also contain product links and discount codes.

Support our work by liking this video and subscribing. And let us know in the comments what you think about any of these 7 gravity filters, or which filters you’d like us to review next. Thanks for watching!