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Review: Grayl Geopress Purifier

Grayl Geopress Purifier

Our bodies are around 60% water, depending on age and gender. Some sources suggest you should drink between 2.5 to 3.5 litres a day, and that’s without adventuring and doesn’t include beer. How can you keep up with that regimen while out in the mountains and still safely avoid unwanted bacteria?  One quick answer would be water purifying tabs or drops that impart a strong taste of chlorine. They often require 30 minutes to take effect, and on a hot day, that 30 minutes can seem like an eternity.  Grayl has a different solution with their  Geopress Purifier.

What is it?

The Grayl Geopress is a very simple, fast and effective filter that’s built into a durable water bottle. It’s made of four separate parts:  the Outer Refill cup (outer dirty water chamber), Geopress Drink Cap, the Inner Press (clean water chamber), and the purifier cartridge.

The Grayl Geopress Cap, Inner chamber and Purifier

The purifier cartridge is made of a non-woven ceramic media fibres. They block particulates while at the same time provide structure for two technologies: positively charged ions and activated carbon. In Grayl’s words, it works, “As dirty water is forced through the media, ion exchange permanently binds pathogens (i.e. virus, protozoa, bacteria). Activated carbon adsorbs chemicals, heavy metals, flavors, and odors.”

The Grayl Geopress Purifier

What does it do?

For those familiar with the Aeropress coffee filter, you will understand what the Geopress is. Fill the outer refill cup with “dirty” water. Combine the filter, Inner Press and cap. Twist the spout 180 degrees. Line the combo up above the outer press, and push down. It’s pretty simple really.

The Geopress Drink Cap



How well does it do it?

True to their literature, the Geopress really does take 8 seconds to press, but not without effort. In order to purify the water we found it best to place the geopress round knee height for leverage. As the other press is rubberized at the base it likely won’t flip off of anything, but it is still best practice to find a flat surface. Place both hand on the Softpress Pads, and lean into it. And don’t be afraid to really lean into it ’cause you’ll have to!

As you continue to use the Geopress it will begin to slow down. This is the filter beginning to fill up with particulates. Grayl rates the Geopress at 350 presses, or 250L. That’s a lot of presses. As our filter began to slow down, up to 25 seconds, we put a knee onto it. Right on the handle, and kneeled on it.  Pressing became easy again and it definitely proved that the bottle’s strong!

At one point on the Great Divide trail we met a group who had run out of water. It was 33 degrees and they had over 10km to go to the next water source that was en-route for them. They only had a drip bag filter system. One of their group came with us with four litres of empty bottles. After two minutes of pressing, we filled his bottles and he was ready to go! There’s no way we could have done that with a drip system.

Yours truly, at the source with a Grayl Geopress


Pros: The Grayl Geopress Purifier is fast + effective. It truly does only take 8 seconds to filter 700ml of water, at least when the filter is new. The bottle is very durable.

Cons: The Geopress is a little heavy. The rubberized bottom catches while placing the bottle in pockets on packs so it’s not suited for frequent sippers.

Overall:The Grayl Geopress is a great filter for the backcountry and for travel to areas where the purity of the water is unreliable. It is well designed for big gulpers or as a main filter for several people.

Interested in the Geopress? Head on over to


  • Removes: 99.9% of Protozoa (Rotavirus, Norovirus and Hepatitis A), 99.9% of Bacteria (E. Coli, Salmonella, Dysentry), and 99.9 % Viruses (Giardia, Cryptosporidium and Amoebae)
  • Filters particulates (microplastics, sediment and silt), Chemicals (chlorine, benzene, chloroform), and heavy metals (lead, arsenic and chromium)
  • The Grayl Geopress purifies and filters 710ml of water in 8 sec.
  • The Purifier cartridge is rated for 350 presses (250L)
  • Filter medium: Electroabsorption/activated carbon
  • Dry weight: 450 grams
  • 10.4 x 5.6 x 3.4 inches


We were provided with a sample for testing but of course this didn’t influence our review in any way.