2021’s Best Gravity Water Filter – 7 Reviews (+ Buying Guide)
Written by: Gene Fitzgerald // Last Updated:
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Gravity water filters are great for home use. But that’s not all. They also allow you to purify thousands of gallons of water from almost any fresh water source like rivers, ponds, and lakes.
And because we find the best ceramic filters among them and they neither require electricity nor external pressure to operate (thus gravity), they’re ideal in emergency situations.
So, how do you find the best gravity water filter? Well, you came to the right place!
In our opinion, the Big Berkey is the best gravity water filter in 2021.
Berkey is easily the most popular gravity water filter brand currently on the market – and rightly so!
Simply put, a Berkey system transforms water from virtually any fresh source – stream, lake, well or tap water – into cleaner, healthier drinking water which is great for everyday life and in any SHTF scenario.
Furthermore, Berkeys come in different sizes but they’re all simple to put together, use, and maintain, and yet highly effective at providing water that easily meets drinking standards. 4.5 stars!
By the way, the perfect size for you depends on how much purified water you need on a daily basis. Larger system equals more water, meaning higher filtration speed and storage capacity.
A Berkey gravity water filter targets water contaminants down to the submicron level:
Pathogenic bacteria (>99.9999%).
Chlorine and chloramine (removed to below lab detectable limits).
Heavy metals like aluminum (>99%), barium (>80%), cadmium (>99.7%), chromium-6 (>99.85%), lead (>99.9%) and mercury (>99.9%).
THMs (removed to below lab detectable limits).
Pharmaceutical drug contaminants such as Acetaminophen, BPA, Progestrone, Ibuprofen (removed >99.9%).
Pesticides and VOCs (removed to below detectable limits).
Rust, sediment, silt, turbidity, taste and odors.
Some of the best overall test results we’ve ever seen. Guarantees very, very thorough filtration.
Filter systems were tested according to NSF standard 53.
Healthy minerals are preserved.
Optional PF-2 filters can be used to remove fluoride and/or arsenic even more effectively.
Choose from 7 system sizes. Larger means higher filtration speed and water storage.
Big Berkey is best suited for families of up to 4 people. Can store up to 2¼ gallons of filtered drinking water. Maximum water production: 7 gallons per hour.
Made from 304 food-grade stainless steel for durability.
Rubber casket prevents scratching on surfaces.
Setup is a piece of cake. No plumbing involved, no tools needed.
Black Berkey filter elements last a full 3,000 gallons or up to 3 years, whichever comes first. High filtration capacity is easy on your wallet and saves you from frequent replacements. Annual cost: ~$40 – super affordable!
Additional PF-2 fluoride filters last 1,000 gallons (set of 2). Annual cost: ~$120.
Lifetime warranty for peace of mind.
Fluoride filters cost a bit more, but fortunately they’re optional.
Frequent filter re-priming may be needed.
Filtration continues even if the lower tank is full. Watch out!
You cannot check how much purified water is left without lifting the upper chamber.
Some people had problems with a leaking dispenser.
If there’s a vacuum, water flow from the spigot may be slow.
Alexapure can keep up with Berkey in terms of overall filtration performance. Comparing lab reports, contaminant reduction rates are almost the same. One important difference: Alexapure is a little less effective at removing toxic lead.
According to the manufacturer, Alexapure gravity filters remove more than 200 different contaminants that can be found in our water supplies today:
Dozens of volatile and semivolatile compounds (99.9+%).
Heavy metals such as aluminum (99.9%), cadmium (99.9%), chromium (98.7%), lead (96.4%).
A whole bunch of pesticides including Glyphosate (99.9%).
All testing according to NSF Standard 42, 53, and protocol P231.
Holds up to 2.25 gallons of clean water.
Stainless steel gives the system the sturdiness it needs + is great to store and conserve water.
Ease of use and easy to assemble.
Filters are 100% made in USA and easy to change for maximum convenience.
Each element is rated at a mind-blowing 5,000 gallons or roughly five years, no priming required. Cost per year: $30 (theoretically).
Filtration elements have a theoretical capacity of 5,000 gallons. However, numerous people said they saw a drastic flow drop within a couple of weeks or months.
For some the filtered water output was “ridiculously slow”, while for others it stopped altogether. In case of the latter, sucking on the filter can help if an airlock is causing the issue. If not, replacement is your only option.
Other complaints include rust spots and slow water flow from the dispenser.
Fluoride filter reduces up to 98% fluoride, up to 99% chlorine, agricultural contaminants, heavy metals like lead (up to 89.1% removal), and pharmaceuticals. Also remineralizes and alkalizes water to boost water pH.
Infuses water with calcium, magnesium, potassium, phosphorus, and other healthy minerals.
Raises pH by around 1.5 – 2.0 units.
Maifan and bio-ceramic mineral stones stabilize and maintain optimal water pH.
2.6 gallons system size is ideal for families.
Material: BPA- & BPS-free plastic.
A few design and quality issues.
Product manual says the gravity filtration system is “Independently tested to NSF 42 and 53 standards” but we couldn’t find a performance data sheet or lab reports.
We read reports from users saying the filtration didn’t do anything when they had tested the product water.
At $200, the average annual filter replacement costs are relatively high, mainly because the fluoride filter lasts no more than 4 months or 317 gallons of water.
Builds up mold. Regularly requires thorough cleaning procedure.
4. Review: LifeStraw Mission Portable Gravity Bag Water Filter
Next, we’ll take a look at the LifeStraw Mission.
In our opinion, it’s the #1 gravity bag water filter in 2021. And thanks to its portability and the fact that it actually removes viruses which is especially important when you’re ion the great outdoors or traveling internationally, the LifeStraw Mission is also our favorite backpacking water filter for both solo and group use. 4.5 stars!
Gravity bag is lightweight and can be rolled up. Easy to carry in a backpack.
Choose between 1.3 and 3.2-gallon bag.
Uses .02-micron ultrafiltration membrane to eliminate waterborne bacteria (99.999999%) as well as parasites, viruses and microplastics (all to 99.999%). Plus, any turbidity down to 0.02 microns will be reduced.
Makes contaminated water potable.
NSF International, EPA, and WHO standards are met. Used by millions of families in rural Africa and other parts of the world.
2 gallons of water per hour means filtration is quite fast.
Great for family use in an emergency scenario and outdoor expeditions.
Extra outlet to flush out dirt.
Red bulb can be used for simple membrane cleaning.
Food-grade quality materials.
Filter capacity: 4,755 gallons which should last a couple of years.
The pH RECHARGE by Invigorated Water is another so-called alkaline water filter, meaning that apart from filtering several contaminants as well as bad taste it increases the pH value of water by up to 2.0+ points – just like the Santevia gravity filter above.
In addition, with its glass body and wooden stand the pH RECHARGE has a great design and clean look. But it also has a few major issues which you can check below. 3 stars.
Uses same PH001 filter cartridges as the pH RESTORE water filter pitcher.
Coconut shell activated carbon, ion-exchange resin, and zeolite remove sediments, chlorine, chloramine, VOCs, heavy metals including lead, organic and non-organic matter, microplastics, and even some fluoride.
Plus, filters contain mineral stones which add beneficial minerals like calcium, magnesium, selenium, and zinc to water for higher alkalinity.
You can add optional PH002 ultrafiltration cartridges (0.01 micron) for more effective fluoride reduction (close to 80 percent) and elimination of 99.9% waterborne pathogens.
Supplies enough water for family use.
Base filtered capacity: 1.25 gallons. Total volume: 2.0 gallons.
Attractive bamboo base and lid.
60-day money-back guarantee.
Numerous complaints about leaky spigots. Feels flimsy. Drips constantly.
Legs of wood stand have to be screwed to the base platform. Provided screws are cheap. Pilot holes didn’t line up for many customers.
Much of the filtered water cannot be dispensed because of tap position.
Lack of NSF certifications with specific contaminant reduction rates.
Water runs through PH001 filters quickly. Filtration might not be really thorough.
PH002 filters tend to clog.
PH001 filters last no more than 96 gallons so that you have to replace frequently. At around $17 per piece, cost will start to add up fast. PH002 filters last a bit longer, 264 gallons, but add to the cost even more.
6. Zen Water Systems Countertop Gravity Water Filter
Zen Water Systems’ countertop gravity filter seems extremely attractive for people on a tight budget, people in need for a low-cost solution to their water contamination problem.
The manufacturer promises that the filter system transforms ordinary tap water into purified, healthy, and great-tasting mineral spring water – truth or fiction?
Well, the Zen does a great job at improving water taste which most people love. But performance-wise it cannot be compared to the cream of the crop. The good news, it comes with added health benefits, e.g. remineralization.
Bottom line: A reasonable choice at such a low price. 3.5 stars!
Zen Water Systems Vitality Gravity-Fed Water Filter
System comes in three different sizes: Four, six, and eight gallons. No matter which version one picks, water quality remains the same.
For example: With 4-gallon system the top container can hold 1.5 gallons, the filtered water tank at the bottom up to 2.5 gallons.
Multi-stage filtration process purifies, remineralizes, and alkalizes water
Contaminants that will be removed include dirt, debris, sediment, bacteria, and VOCs. Silver impregnated granular activated carbon filters chlorine, chloramines and other chemicals, improving water aesthetics and inhibiting the growth of bacteria.
Normal flow rate is approximately 45 to 60 minutes for a full tank. Plenty of water for an entire family.
Spigot is magnetic in case you swear by magnetized water.
One definite advantage over Berkey and the other filters: You can see inside the system so you can tell how much water is left in the holding tank. This makes it a lot easier to manage.
Setup isn’t complicated, although it takes a little bit longer due to the many different parts that need to be assembled.
The mineral stones require boiling prior to first use.
All in all, the average annual filter replacement cost seems reasonable (around $70).
Everything is 100% BPA-Free.
Leaking and broken spigots – they just tend to not last very long and are costly to replace – are the main issues.
System is made of plastic for the most part. We would have preferred stainless steel.
Quality-wise, the build of this unit doesn’t look as good as any of the Berkey filtration systems.
We’ve checked the company website and product manual but couldn’t find any hint about independent lab tests or third-party certificates.
Higher maintenance needs.
Entire system requires cleaning about twice a year.
Mineral stones need to be rinsed, boiled and dried.
Ceramic filter dome needs to be cleansed.
To fill a glass of water you need to place the system near the edge of your kitchen countertop. Not very well thought through.
30 days warranty for a gravity-fed water filter is extremely short.
7. Propur Big Gravity Water Filtration System with Dispenser
Just like Berkey, Propur gravity filters can be fed with water from just about any source including tap, lake, stream, river, pond, or rain water. What’s more, they’re easy to use and do an outstanding job at removing even the most stubborn contaminants providing H2O of great purity that also tastes delicious.
That said, for our final verdict we must take into account all drawbacks listed below. Our final rating is 3.5 stars!
Propur Scout filter system is ideal for one person on the go. Stores up to 55 ounces of water.
The Traveler filter can hold more than 3 times the amount of water that goes into the Scout.
Next in line is the Propur Nomad filter which combines good portability with higher flow rates.
The Propur Big is the most popular version and perfectly sized for everyday use by a whole family.
And lastly the King which can be expanded to 4 filters for very high water consumption. Can hold almost 4 gallons total.
The larger the system, the more purifier elements it can host for higher filtration speed. Larger units also apply larger filters which again increases the amount of water that can be processed in a given period of time (0.18 gallons in one hour for the smallest filter versus 0.9 gallons for the largest).
Won’t affect water purity.
All Propur gravity filters work with ProOne® G2.0 ceramic filter elements combining granular activated carbon based media with silver-infused ceramic.
They all remove the same things. This also goes for regular versus SLIMLINE filter versions (designed for emergency cases).
Most important water pollutants that will be eliminated are VOCs (>95.0%), TTHMs (99.0% on average), aluminum (98.0%), arsenic(III) and arsenic(V) (99.7%), lead (99.9+%), sodium fluoride (97.5%), pesticides, semivolatile contaminants (97.0+%), chlorine and chloramines (99.9+%), nitrites & nitrates, herbicides, pharmaceuticals and PFOA & PFOS (99.9+%), a handful of waterborne pathogens, and so-called emerging contaminants.
Testing requirements for NSF standards 42, 53, 401, and protocol P231 were met – we love it!
All filter models feature 304 stainless steel containers (polished or brushed finish) for durability.
Initial setup and replacing filters is a breeze.
Filtration capacity per cartridge: Between 6 and 12 months, depending on which size. Cost estimate: $150-160 each year.
Larger filters last longer due to their larger surface area.
Except for the Propur Scout, all steel components are backed by a limited lifetime warranty.
Compared to the competition, filters are rather pricey.
Slow filtration (to be fair, thorough filtration takes time) – Try to filter water overnight and follow instructions regarding filter priming. It might also be that the lid sits too tight not allowing air to flow inside for pressure compensation.
Unpleasant or funny water taste.
According to Amazon reviewers, Propur customer support is unresponsive at times.
Buying Guide: Things to Consider Before Buying a Gravity Water Filter
What is it that you should consider before buying a gravity water filter?
Indoor or Outdoor – How Will You Use Your Gravity Water Filter?
Are you planning to use your new gravity water filter indoors or outdoors?
What difference does that make? Well, depending on the application you’ll likely be facing a completely different range of water contaminants.
For example: Most tap water is chlorinated or chloraminated to kill waterborne pathogens. So while you don’t have to worry about bacteria and viruses, you probably want to get rid of that unpleasant chlorine taste and smell.
On the other hand, if you like camping in the backcountry where you don’t have access to a safe freshwater source, a gravity water filter needs to be capable of removing dangerous bacteria, protozoa, cysts, viruses etc.
Simply put, the filter you buy needs to be designed for the purpose you’re intending to use it for. Or, you buy an all-rounder like the Berkey which basically removes all the contaminants from tap water, well water, and water sources like rivers and lakes.
NSF Testing & Certifications
Personally, we like to rely on SF testing/certifications when it comes to filtration effectiveness. Otherwise, brands and manufacturers can make claims all day long about which contaminants their water filtration systems remove. Reality is, only independent lab testing can provide proof.
In the realm of gravity water filters, these are the most important NSF standards you should look out for:
Standard 42 – For water aesthetics. Most importantly, measures the reduction of chlorine.
Standard 53 – For contaminants with health effects. The standard covers reduction of lead, chromium 6 and other heavy metals, all kinds of chemicals, organics, microorganisms, and much more.
Standard 401 – For emerging contaminants. Addresses removal of pharmaceuticals, pesticides, and other chemical compounds that can also have health effects.
Standard 244 – For microbiological contamination. Bacteria, viruses, cysts, protozoa – you name it.
Protocol P473 – For PFOA and PFOS reduction.
Gravity Filters Flow Rate
We get it; fast filtration without long waiting times seems desirable. However, most filter media require a long-enough contact time with the water to pull out as many contaminants as possible.
In other words: Thorough filtration takes time. But don’t make the mistake and confuse thorough filtration with low quality, clogged filters that won’t let any water pass through.
Filter Life & Replacement Frequency
We like long-lasting filters as they save you time and money. Black Berkey purification elements, for example, last up to 3,000 gallons or 3 years. Compare that to the 96 gallons you get out of the PH001 filter cartridge by Invigorated Water.
Our tip: When shopping for a gravity water purifier also check capacity, price, and availability of replacement filters.
Portability + Storage Tank Capacity (a.k.a. Weight and Bulk)
A filter’s portability becomes important when you’re thinking about using it outdoors.
The two main factors that determine portability are physical size and weight. Obviously, the smaller and the lighter, the better.
At the same time, a small system means low storage tank capacity and in some cases even slower filtration speed. Thus, if all you want is a gravity filter for your kitchen countertop, we recommend you go for a larger unit for maximum convenience.
When it comes to gravity filtration system materials, food-grade stainless steel and glass are our preferred choices. We don’t really like plastic, even if it’s free from BPA and BPS.
Gravity Filter Design
First and foremost, a cleverly designed system is easy to use and maintain.
The exact opposite of clever design is when the spigot of a gravity water filter system is positioned too high so that much of the filtered water cannot be dispensed.
More on Gravity Water Filters
What Is a Gravity Water Filter?
First of all, what is a gravity water filter?
Just like a water filter pitcher, a gravity water filter relies on gravity to force water from an upper chamber through one or more filtration elements into a lower storage tank. The filtered water can then be dispensed via a simple spigot.
The main advantages of a high-quality gravity water filter is that it make water safe(r) to drink and greatly improves aesthetics without the need for electricity or water pressure from a faucet or pipe. Certainly the main disadvantage is that you have to refill each system manually.
How about installation and maintenance? Don’t worry, gravity filters are quick to assemble and all they need for maintenance is a good cleaning every now and then.
How Do Gravity-Fed Water Filters Work?
The Different Types of Gravity Water Filters on the Market
As we said, regular gravity water filters use gravity to force water from an upper chamber through one or more filter elements into a lower storage tank ready for dispensing.
Gravity filter bags are just a tiny bit different: They consist of a bag to fill in the feed water and a hose with a filter element attached. If you open the valve water is filtered on demand. Some gravity filter bags also feature a second bag to store the filtered water in.
As far as the filtration process is concerned, some gravity filters rely on a ceramic filter element, some on activated carbon, some additionally mineralize the water, and so on.
Benefits and Disadvantages Gravity Water Filters
Clean Drinking Water
Obviously, the most important benefit of a gravity filter is that it gives you access to clean drinking water, at least if the filtration process is solid – clean water means mostly free from potentially harmful contaminants that may otherwise affect the health of your family.
Improve the Taste and Smell of Water
In addition to filtered water being healthier, it also tastes and smells much, much better. For improved tap water taste and odor, efficient chlorine removal is key.
If you receive water from a private well, you might be dealing with organic contamination, or high iron, manganese, and hydrogen sulfide content. A good gravity filter can easily eliminate these contaminants.
Great for Emergencies
A benefit specific to gravity filters is that they’re great for emergency situations as they require neither electricity nor a functioning plumbing system to work. So if sh*t hits the fan and you’re the proud owner of a Berkey system or something comparable, all you need is a nearby freshwater source to feed the filtration process.
Using any home water filter is a lot more eco-friendly than buying bottled water and producing plastic waste. Above that, many bottled waters are literally plain tap water filled into a water bottle, so why even bother?
Another reason to invest in a countertop gravity water filter or any type of water filter really is reduced cost. Buying bottled water is just so much more expensive than investing your money in a high quality water filter system. And yes, we’ve taken into account expenses for replacement filters.
Probably the main disadvantage of using a gravity water filter is that you have to refill it manually. Many people don’t see a problem in that, but some may consider it inconvenient.
Slow Water Output
Remember that we mentioned that thorough filtration takes time? It may take even longer with gravity filters. That’s because the pressure created by gravity force is nowhere near as high as water pressure in your home’s plumbing system.
Assembly & Maintenance
How to Assemble a Gravity Filter System
Putting together most gravity filter systems is a breeze. It can be done without tools in 5 to 10 minutes. As an example, here’s how you assemble a Berkey:
Wash your hands before proceeding.
Attach lib knob.
Insert washer onto threaded end of dispenser.
Insert spigot into hole of lower chamber.
Insert washer to threaded end of dispenser from inside lower chamber.
Secure spigot with nut.
Hold nut from inside and turn spigot upright.
Install plugs into holes that won’t accommodate filter elements.
Prime filter elements (see below):
Press circular priming button onto threaded stem of filter element.
Carefully press filter with priming button on top against a faucet.
Slowly turn on cold water.
Wait for water to run down filter side.
Wait another 5 seconds and repeat process with next filter element.
Install filters to holes in upper chamber using washers and wing nuts.
Place upper chamber on top of lower chamber.
Fill water into upper chamber.
Place lid on top.
Maintaining a Gravity Filter
What do you need to do to keep your gravity filter system in good shape?
Again, using Berkey as our prime example, each filter element requires cleaning every now and then. Frequency depends on the quality of your water like turbidity and sediment content. Whenever filtration speed starts to decrease significantly, it’s probably time for another cleanse.
Simply remove the filter(s) and scrub the exterior with a brush or scouring pad. The idea is to remove the outside layer which absorbed the vast majority of impurities. If scrubbing doesn’t work, you can use a vegetable peeler to peel away a thin layer under running water.
When you’re done, keep in mind to re-prime each filter element before reinstalling.
Another essential task is washing the upper and lower chamber with soapy dishwater, about monthly.
Berkey vs Alexapure vs Propur vs Zen Water Systems
We have to admit that we love Berkey systems because they provide the full package: Fair price, durable materials, thorough filtration removing a broad range of water contaminants, high portability, and long-lasting filters that are easy and affordable to replace.
Alexapure gravity filters can compete with Berkey in terms of overall contaminant removal, but there have been quite a lot of complaints about clogged filters. And if you’re forced to replace cartridges more frequently costs increase.
As for Propur, again, filtration is pretty solid – Propur gravity filters can be fed with tap, lake, stream, river, creek water… – removing even the most stubborn contaminants, but the filters are more expensive. On top of that, we read reports about leaky spigots, rusty steel tanks, and slow water flow.
Lastly, Zen Water Systems. These guys simply cannot compare with any of the above competitors from a water-quality perspective. Plus, Zen water systems are mainly plastic. We would only recommend them is if you’re super into alkaline drinking water.
Gravity Water Filters: Frequently Asked Questions (FAQ)
Are gravity based water purifiers good?
They are. Because filtration is slow, the water has a long contact time with the filter media which makes the process highly effective. For example, the lab test results for the Black Berkey water filter elements are some of the best we’ve ever seen.
How do you use a gravity filter?
You simply fill “dirty” water into the top reservoir and let gravity do the rest. It’ll push the water through the filters (where it’s cleaned) and into the lower storage tank – just like a pitcher water filter.
How much does a gravity filter cost?
This mainly depends on its size and construction materials. Anywhere between $100 and $350 is realistic. Although, if you opt for a portable gravity water filter, you might have to spend less than $50 USD.
How do you make a gravity water filter?
Actually, we wouldn’t recommend making your own gravity water filter. I mean, at least buy the filter elements from a reputable source providing real test data. For the rest of the setup, you could use stainless steel pots. Just make sure that the dirty water doesn’t contaminate the drinking water.
Questions about gravity water filters or any other type of water filter? Ask away!
And keep in mind to revisit this buying guide from time to time since we’re going to review new gravity water filters occasionally.
Gene Fitzgerald has been with BOS since the very beginning. She is head of content creation and has fully immersed herself into the home water treatment industry only to become an expert herself. Outside of BOS, Gene loves reading books on philosophy & social issues, making music, and hiking.
Learn more about Gene and the rest of the BOS Team.