Platypus GravityWorks

Do you need a water filter or water purifier? 

• Filters: Physically remove protozoa (like Cryptosporidium and Giardia lamblia) and bacteria (such as E. coli, Salmonella, Campylobacter and Shigella)—the main water concerns if you’re traveling in the U.S. and Canada. 

• Purifiers: Go further by combating viruses such as hepatitis A, rotavirus and norovirus. 

Types of water filters 

• Pump: Precise even from shallow water sources, replaceable internal element or cartridge. Can be bulky and a chore to use and clean in the field. 

• Gravity: Easy to use, filters large quantities of water, replaceable element. Needs a hang point, slower and harder to fill in shallow water sources. 

• Ultraviolet light: Easy, quick and no element to replace. Requires batteries, prefiltering for silty or cloudy water and multiple treatments for large quantities. 

• Bottle: Lightweight, quick, replaceable element, less pricey. Water quantity is limited by bottle size. 

• Squeeze: Easy, quick, smaller and less pricey, have replaceable elements, sometimes usable as both a gravity and straw-style filter. Water quantity is limited by reservoir size. 

• Straw: Easy, quick, lighter and less pricey. Water is only available when you're at a water source and not all models have replaceable elements. 

• Chemicals: Easy, inexpensive, ultralight backup method to purify water. Significant wait time before water is safe to drink and don’t taste great.