Water & light

Choosing a water filter for trekking

A filter is lighter than a day of bottled water and works at every stream along the way.

Straw or squeeze

A straw filter is the simplest: you drink directly through it. A squeeze filter fills bottles and cooking pots, which is easier for a group.

What filters remove

Hollow-fiber filters like these remove bacteria and protozoa, but not viruses or chemicals. Near villages or livestock, boil water or add purification tablets as well.

Cold weather

A filter that freezes with water inside can crack. On cold nights, keep it inside your sleeping bag.