Aquamira 水滴消毒液

Two drops per liter and you're set, which is way less fiddling than the tablets I used to deal with. Treated a full 30 gallons over a week of backcountry refills and never got sick once. The little bottles have barely gone down.

Carried this on a four-day trip and treated about 30 gallons of creek water without running out once. The chlorine dioxide taste fades faster than iodine tablets I've used. Two tiny bottles weigh next to nothing in the pack.

Took these on a four-day backcountry trip and treated about 20 gallons total without any issues. The two-part dropper system is a little fiddly at first, but once you get the hang of it the water tastes clean with zero chlorine aftertaste.