Squeeze filters, straw filters, and pump filters are all great for turning questionable water clear, but they all require the use of your hands and take up your valuable time. Gravity filters, however, offer a convenient hands-free solution. Instead of forcing water through your filter, a gravity system lets gravity do the work of pulling the water down from a hanging reservoir, through a water filter, and into a waiting receptacle.
We like the freedom that gravity filters give us to accomplish other tasks while water filtration duties are delegated to gravity, so we went looking for the best ones to bring with us when we need sanitary water. We learned a lot during our testing, and we’ve compiled all of it into the following seven reviews. Hopefully, once you’ve read them, you’ll know exactly which gravity filter to add to your gear setup.
Comparison of the Winners in 2021:
|Best Overall||Platypus Gravity Water Filter||
|Best Value||Katadyn BeFree Gravity Water Filter||
|Premium Choice||Berkey Gravity-Fed Water Filter||
|Sawyer Gravity Water Filtration System||
|LifeStraw Flex Gravity Water Filter||
The 7 Best Gravity Water Filters:
1. Platypus Gravity Water Filter – Best Overall
The GravityWorks water filter system from Platypus is an all-in-one system that includes the dirty water and clean water bags, as well as the filter and hose to connect them. It weighs 11 ounces in total, which is a bit heavy for this type of system. But we’re willing to carry a few extra ounces, for the extra ounces that these reservoirs provide. They can each hold four liters of water, so you’ll be able to collect and filter over a gallon of water at a time.
This filter removes over 99% of bacteria and protozoa, making it a great choice for use on trails. With a flow rate of 1.75 liters per minute, it won’t slow you down when you’re trying to make miles. You also won’t have to replace the in-line filter often since it lasts for 1,500 gallons. In our testing, it turned murky water crystal-clear, and it passed the taste test even when the original source smelled less than pleasant. Overall, we love the fast filtration, large capacity, and clean water it produces, which is why it has earned the top position on our list.
2. Katadyn BeFree Gravity Water Filter – Best Value
Katadyn is well-known among hikers and backpackers and we knew the BeFree Filtration System would be good, we just didn’t know how good. It’s a very simple system that doesn’t require any hoses. It consists of a large three-liter bag with a filtering nozzle mouthpiece. The cap on the mouthpiece pops open to allow the water to pass through at a high flow rate of two liters per minute.
We loved this nozzle because of its versatility. You can drink straight from the bag if you want, no other tools needed. You can hang it and let it drip, but unlike other bags, you don’t have to hang it high. You can hang it just above a waiting water container and you’ll be fine. You can just pour from the bag into your container and it will work.
The filter needs no backflushing. You just shake it clean if the flow slows down and it’s good to keep working. But each filter lasts for just 260 gallons, which is on the shorter end of filter lifespans. But the simplicity, versatility, high flow rate, and affordability of the Katadyn BeFree filter make it the best gravity water filter for the money.
3. Berkey Gravity-Fed Water Filter – Premium Choice
The Travel Berkey is a premium device that costs a car payment to get started with. It’s supposed to be portable, but in reality, it’s too large to be very portable. At four pounds and 18 inches tall, it’s the biggest filter on our list by a long shot. But this filter can produce some of the purest and most delicious water of any gravity filter we tested.
Where this filter shines is its filtration. The Berkey system can remove over 99% of bacteria and protozoa like many of the backpacking gravity filters can, but Berkey goes a step further. This filter can also remove over 99% of all viruses, which is something very few filters are capable of. It also removes pharmaceuticals and add-on filters are available to remove fluoride.
Even though this is an expensive device, you get a lot of use from it without needing maintenance or filter replacement. These filters are good for 6,000 gallons between replacements. But if you’re drinking murky water, expect them to fill up faster and need replacing sooner.
4. Sawyer SP160 Gravity Water Filtration System
The Sawyer SP160 Gravity Water Filtration System utilizes their popular MINI water filter attached to a one-gallon bladder by a hose. This offers you a lot of versatility since the MINI can be used in many ways. You can use it as a gravity filter, but there’s no clean water reservoir included. It can be used in-line on a hydration pack or you can drink straight from the water bladder. Alternatively, you can take it off and screw it onto a water bottle if you want a change of pace.
This filter is good for 100,000 gallons with no replacement cartridges. Just backflush it when the flow rate slows down, and it’ll be back to full flow. The entire setup with filter, bladder, and hose weighs just seven ounces, making it one of the smallest and most portable gravity water filters we tested. Plus, it filters down to 0.1 microns, so it’s also very thorough and will keep you safe in questionable situations.
5. LifeStraw Flex Gravity Water Filter
LifeStraw is one of the most well-known names in personal water filtration. The LifeStraw Flex Advanced Gravity Water Filter attaches the LifeStraw Flex to a thick, durable water bag by hose so that you can filter water through it. The bag has a strap for easy hanging, but there’s no clean water reservoir to collect the filtered water in.
One thing we like about this system is that the filter can be used as more than just a gravity filter. You can use it in-line with a hydration pack or even screw it onto a water bottle. The main filter membrane is good for 500 gallons, but there’s a second carbon filter that only lasts for 25 gallons between replacements. That’s more upkeep than we prefer, which loses the LifeStraw Flex some points.
The included water bag is very robust and unlikely to rip. Even better, it’s got a large capacity that allows you to filter a gallon of water at a time. But that will take quite a while since this filter has a pretty low flow rate compared to many of the others we tested.
6. MSR AutoFlow Gravity Water Filter
We like a lot of products from MSR, but the AutoFlow Gravity Water Filter isn’t one of our favorites. It’s one of the most expensive options we tested, but for the price, we think there are better choices. That said, there were still things we liked about this filter.
The AutoFlow is available in a two or four-liter capacity, depending on your needs. Its reservoir is made well and won’t leak with a roll-tight buckle-enclosure top. But there’s no clean water bag to collect your filtered water in. That makes things difficult since you can’t drink straight through this system like you can with some of the more versatile gravity water filters we tested.
With a flow rate of 1.75 liters per minute, this filter is no slouch. It’s faster than some of its competitors, but not the fastest we tested. It also needed backflushing more often, which is very difficult with this style of filter. Overall, we don’t think it’s the best choice, especially since it’s one of the most expensive options but doesn’t offer the same features as other cheaper models.
7. miniwell L630 Gravity Water Filter
This kit from Miniwell includes everything you need to use their L630 water filter as a gravity filter or filtering hydration bladder. It’s reasonably priced for what you get, and it’s a versatile design that takes cues from the Sawyer MINI and LifeStraw Flex. Like those filters, this one can also be screwed directly onto a water bottle.
The miniwell filter has a lifespan of 500 gallons, far less than the Sawyer MINI it’s modeled after. The flow rate is also considerably reduced on the miniwell, which only manages to produce 0.6 liters per minute of filtered water.
You do get a clean water reservoir with this kit, but it’s much smaller than the slide-lock dirty water bag, which we also weren’t big fans of. The slide-lock is slow to operate, though it does seal well. Overall, this is a good try at copying some great filters, but the originals did it much better.
While all these filters may perform the same function and do so in a similar fashion, there are still significant differences that separate them. So, what differences might make one preferable to another? After testing so many, we think we know exactly which traits you should prioritize when choosing a gravity water filter, so let’s discuss them so they’re at the forefront of your thoughts.
This is one of the most important traits for your filter to have. A gravity-fed filter isn’t going to be much help if it takes 15 minutes to produce a bottle’s worth of water. Some of the filters we tested could produce as much as two liters per minute, allowing you to filter an entire gallon in just two minutes. That means it can provide enough water for an entire group when camping, which makes it very useful.
Before deciding on a filter to purchase, consider where you plan to use it. If you’re going to take it with you on hiking or backpacking trips, you need a small filter that doesn’t take up much space and weighs very little. But if you’re just going to be using it for car camping, RVs, or even hotels, then size and weight won’t be such a serious issue.
Ease of Use
It doesn’t matter how good a filter is if it’s too difficult to use. If your filter is overly complicated, you’ll be less likely to use it. When you’re tired and thirsty, you don’t want to be wrestling with difficult filtration devices. Look for something that’s easy to use so it doesn’t take long to set up and never a hassle in the heat of the moment.
Many of these filters have replaceable cartridges with varying lifespans. If your filter doesn’t have a cartridge, then the filter lifespan is even more important. Some cartridges have short lifespans and need replacing every 25 gallons while other filters can last for thousands or even hundreds of thousands of gallons. A full filter can be a major setback on the trail with no replacements, so we prefer filters with longer lifespans.
All filters are not created equal. Some may remove bacteria and protozoa down to 0.2 microns, sometimes less. But others are capable of 0.1-micron filtration while some of the premium filters can even remove viruses. While it’s great that you can get a portable filter that removes viruses, you’re unlikely to need that protection, so it pays to know what you’ll be trying to remove from your water.
These are all gravity water filters, but what if you want to use it as something else? We love versatility, so filters that have various uses are always our favorites. Some of these filters can be screwed onto water bottles, used in-line with hydration packs, or just drink from water sources like a straw. While they may be intended as gravity filters, the extra versatility can pay off in many situations, like when there is nothing in sight that’s tall enough to hang your water bladder on.
Gravity-fed water filter systems can make it easy to get filtered water when you don’t have access to filtered faucets and home filtration systems. We tested a lot of different gravity filters while trying to find the best ones. You’ve already read our reviews comparing seven of our favorites, but we’re going to mention our favorites again so they’re fresh in your mind. Our top recommendation is the Platypus GravityWorks Water Filter System. We liked its large four-liter clean and dirty water reservoirs, it’s impressive 1.75 liters per minute flow rate, and the 1,500 gallons of water we could filter between cartridge replacements.
For the best value, we think it’s hard to beat the Katadyn BeFree Filtration System. It shakes clean so no backflushing is necessary and filters at a rate of two liters per minute. It’s also versatile and allows several methods of use with no hoses or other bags needed.
If you want a premium filter that even removes viruses, the Travel Berkey is our top pick. Its filters remove viruses, pharmaceuticals, bacteria, protozoa, and more, and they’re good for 6,000 gallons between replacements.
Pete has been working in the trades since high school, where he first developed a passion for woodworking. Over the years, he has developed a keen interest in a wide variety of DIY projects around the home. Fascinated by all sort of tools, Pete loves reading and writing about all the latest gadgets and accessories that hit the market. His other interests include astronomy, hiking, and fishing.
As the founder of House Grail, David’s primary goal is to help consumers make educated decisions about DIY projects at home, in the garage, and in the garden.
- 1 Comparison of the Winners in 2021:
- 2 The 7 Best Gravity Water Filters:
- 2.1 1. Platypus Gravity Water Filter – Best Overall
- 2.2 2. Katadyn BeFree Gravity Water Filter – Best Value
- 2.3 3. Berkey Gravity-Fed Water Filter – Premium Choice
- 2.4 4. Sawyer SP160 Gravity Water Filtration System
- 2.5 5. LifeStraw Flex Gravity Water Filter
- 2.6 6. MSR AutoFlow Gravity Water Filter
- 2.7 7. miniwell L630 Gravity Water Filter
- 3 Buyer’s Guide
- 4 Conclusion: