Having access to safe drinking water is important. Worldwide, more than 2 billion people get sick from poor quality drinking water due to diseases like cholera, typhoid, or diarrhea. Here in the US, pathogenic bacteria like E. coli and salmonella are present in most water sources.
Which is why if you’re backpacking in the wilderness, it’s essential to have a drinking supply that’s clean and potable. If you don’t mind carrying more weight, you can bring your own supply but if you prefer to keep it light, a gravity water filter is your best option.
That’s because this type of filter is lightweight, portable, and easy to use. Gravity water filters essentially rely on gravity to remove contaminants from the polluted water. Among backpackers, a typical gravity water filter would consist of an upper bag for feed water, a lower bag where the filtered water will be stored, and the mediator with the filter elements in between.
The upper bag is filled with raw water and then hanged on a tree. Gravity then pulls the water down through the filter element where its microscopic pores will trap the contaminants, allowing only the water molecules to pass into the water reservoir bag. This is how you get to have potable drinking water.
If you're at home, there are the countertop types. Some models come with spouts or spigots; others feature more fancy filters. Some will also remove chlorine, mercury, and copper along with the bacteria. But, some are also designed to remove heavy metals like lead. These types are best for those who live in communities with contaminated water sources or for households trying to live off the grid.
The best ones are those that also purify rather than just filtering. The pores in their filter elements are smaller than the usual so that they are able to capture viruses, which are smaller than bacteria.
Nowhere are these water filtration systems more useful than in emergency preparedness kits. Relief agencies worldwide have used them in their disaster response services because they’re easy to set up and use because there is no plumbing required.
When picking your gravity water filter, pick one that best fits your needs. In this post, I’ve listed both personal and countertop types which have some important elements. They all filter water efficiently, but some of their features have additional advantages.
Here are my top five choices of the best gravity water filters on Amazon.
The Best Gravity Water Filters
- Travel Berkey Gravity-Fed Water Filter
- Platypus GravityWorks High-Capacity Water Filter System
- Santevia Gravity Water System
- TRK Drip Ceradyn Gravity Water Filter
- Doulton Household Gravity-Fed Water Filter
1. Travel Berkey Gravity-Fed Water Filter
This is a portable water filtration system that filters and purifies water for about 1-3 people each day. It can hold about 1.5 gallons and takes about 2 hours to filter a full bag.
It does not only filter out pathogenic protozoans like giardia and cryptosporidium but will also trap heavy metals like arsenic and lead, drugs like acetaminophen, and viruses too. According to the manufacturer, it will also remove or reduce pesticides, VOCs, petroleum products, perfluorinated chemicals, rust, silt, sediment, and even radiologicals in your drinking water.
It’s easy to use and lasts for a long time. A pair of its purification elements will last up to 6,000 gallons before needing replacement. It’ll also save you money too. You’ll end up spending an average of only 2 cents per gallon of purified water.
The Black Berkley Purification element comes with a 2-year prorated warranty calculated in 6 months intervals.
- Has a very fine filter which can also capture viruses
- Ideal for use in purifying heavy metal contaminated drinking water
- The filter needs to be handled carefully; the stem at its base will easily break off if mishandled or dropped
- The set doesn’t include a flouride filter; you have to buy it separately
2. Platypus Gravity Works High-Capacity Water Filter
This gravity water filter is best suited for group camping and for emergency preparedness kits. It has an 8-liter capacity and produces 1.75L of clean water per minute.
Made in the USA, it uses a Hollow Fiber design that bundles hundreds of hollow fibers into a single filter. This increases its surface area up to 18 times more than traditional filters.
Its filter pore size is 0.2 microns and it meets the EPA standards for filtering 99% of bacteria and 99.9% protozoa, including cholera, E. coli, and salmonella. It’ll also last for 1,500 liters or 396 Gallons.
It’s also easy to use. When outdoors, just fill the 4-liter dirty water reservoir, hang it from a tree and watch the 4-liter clean water reservoir fill with filtered water in just 2.5 minutes.
- Easy to use; no need for pumping
- Very lightweight
- Doesn’t filter viruses or chemically contaminated water
- The filter is advanced but delicate; not for use in cold environments below 32°F (0°C)
3. Santevia Gravity Water System
This is a countertop water gravity filter equipped with a filter that can reduce fluoride and chlorine by up to 98%.
Its upper tank can hold about 5 liters/1.3 gallons of dirty water while the lower tank is capable of storing 10 liters/2.6 gallons of filtered, clean water. It uses a ceramic pre-filter that has a 0.3 micron pore size which is more than enough to filter out rust, sediments, bacteria, and even microplastics!
A unique feature of this brand is that it claims to filter water the same way that nature filters mountain spring water. They’ve developed a filter that has a 6-stage purification process:
- Stage 1 filters out bacteria and parasites
- Stage 2 removes chlorine, color, and particulates through the use of activated carbon and charcoal
- Stage 3 alkalinizes the water by filtering it through silica sand
- Stage 4 takes out heavy metals by using a zeolite granule layer
- Stage 5 infuses it with ionized minerals to oxygenate the water
- Stage 6 uses a bio ceramic brae for final filtering
The final filter, however, is not included in this model and must be purchased separately. But even without this special multi-stage filter, this filtration unit will still be able to produce clean water quickly and efficiently. One user said that it took about 2 hours for the whole upper tank to filter to the lower section.
- Filters microplastic
- Its fluoride filter does not leave an aluminum aftertaste, unlike most filters in the market
- Filters have short lifespans; the shortest is the fluoride filter which is only good for four months
- Requires tedious cleaning; mineral rock filter, for instance, needs to be boiled in order to sterilize it
4. TRK Drip Ceradyn Gravity Water Filter
This is a portable water filter that has been field tested to produce up to 150,000 liters under the harshest conditions. This is a Swiss-made product that markets itself as the top choice for military and relief agencies worldwide .
It uses three 0.2 micron silver-impregnated ceramic filters that meet the EPA standards for removing 99% of bacteria and protozoan cysts from contaminated water. It’s also engineered to withstand cleaning in the field. It can be scrubbed time and time again.
The water filter is also easy to use. The upper compartment can be filled with up to 2.5 gallons of untreated water. Just fill it up and the water will just drip through the ceramic filter and into the bottom compartment. Its holding tank can hold up to 10 liters of filtered water, making it ideal for base camps or cabins without running water.
- Easy to set up and use
- Durable ceramic filters; users say it will almost last forever
- Doesn’t purify water of viruses, heavy metals or minerals; it won’t improve the taste of water
- Poor flow rate; only good for producing drinking water for 6 people, not for domestic use
5. Doulton Household Gravity-Fed Water Filter
This is a low cost gravity water filter that has a 4.2-gallon capacity. It uses a sterasyl ceramic candle 0.9-micron filter that removes 99% of suspended solids, water borne protozoan cysts, and pathogenic bacteria from contaminated water. The candle also contains silver to inhibit bacterial growth so you don’t have to boil it to sterilize.
Its filter is engineered to last long. It can be cleaned and reused to produce more than 5,000 gallons of filtered water.
It’s also compact and portable. The manufacturer says that all of Doulton ceramics are made from 100% natural elements. This filter unit also comes with 2 polypropylene food grade containers with snap on flat lids for easy water storage.
- Easy to install and use
- Less expensive than most countertop gravity water filters
- One user says it takes 24 hours to filter a full load
- Another said that the container lids need to be tightened carefully in order to prevent leaking.
Buyers Guide to Picking the Best Gravity Water Filter for Your Drinking Needs
Type of Filter
How small are its pores? The usual standard is 0.2 microns and that’s enough to filter out usually 99% of bacteria and particulates. But if you want something that can also trap viruses, look for something smaller than 0.2.
Some models will use a more complicated filtration mechanism to filter out toxic heavy metals or carcinogenic pesticides. Others will combine a mixture of elements, like ceramic impregnated with silver. This makes the filter self-sterilizing, so you don’t have to clean it.
Countertop models will have more specialized filters which can do more than filter your water. Some models can be equipped with multi-stage filters that can also turn the water alkaline.
Look at the number of gallons it can filter before it needs to be replaced. Then calculate how often you will replace it based on your water use.
If you’re looking at a filter that uses several filtration elements, check the lifespan of each element since they all have different capacities and lifespan.
Also note if the filters are easy to replace. Some models tend to have filtration elements that easily break. Pick the ones that have been tested under field conditions.
In general, it takes 40 minutes for a gallon to fully filter down into the water reservoir chamber. If you plan to use the gravity water filter on a hiking trip, you might want to look for a filter that has a much faster flow rate.
Plastic and stainless steel are usually used for making the upper and lower chambers of a gravity water filter.
Stainless steel is more durable, yet some models use steel that’s easily dented. But stainless steel is also safer than plastic because it doesn’t leach chemicals into the water.
That’s not to say that all plastic water filters are dangerous. The type of plastic being used is essentially food-grade quality, so you can be sure that nothing will leak into the water. Still, it’s best to pick the ones that have a BPA-free label.