Consumer Reports

If you've got time to wait for your potable water, the Aquamira Water Treatment Drops is a lightweight and inexpensive travel system used by many thru-hikers. Treatment is simple: activate the substances, then drop them into your water and wait. It kills the most bacteria of all the chemical treatment systems we tested, including cryptosporidium cysts when given ample time. When doubled with a filtration system, these drops can easily be used anywhere in the world. Plus, they are inexpensive and incredibly packable. There is no need to do field maintenance, and the drops inherently never clog, which are bonuses that increase their reliability.
Unfortunately, chemical treatment doesn't filter out particulates, so we recommend carrying a pre-filter or a handkerchief to assist with that work. While it's advertised that treatment time is just 15 minutes, you have to wait much longer &#40;four hours is recommended&#41; to get rid of hard-shelled cryptosporidium cysts. These drops are definitely our favorite chemical treatment for backcountry water due to their packable design and ease of use &mdash; just make sure you have time to wait for your sterilization. The Aquamira Treatment Drops offer a great value for a couple of trips into the backcountry, but if longer-term value is what you're seeking, one of the other systems in our review may be a better fit, though it will mean a higher up-front cost. 

OutdoorGearLab

If you've got time to wait for your potable water, the Aquamira Water Treatment Drops is a lightweight and inexpensive travel system used by many thru-hikers. Treatment is simple: activate the substances, then drop them into your water and wait. It kills the most bacteria of all the chemical treatment systems we tested, including cryptosporidium cysts when given ample time. When doubled with a filtration system, these drops can easily be used anywhere in the world. Plus, they are inexpensive and incredibly packable. There is no need to do field maintenance, and the drops inherently never clog, which are bonuses that increase their reliability.
Unfortunately, chemical treatment doesn't filter out particulates, so we recommend carrying a pre-filter or a handkerchief to assist with that work. While it's advertised that treatment time is just 15 minutes, you have to wait much longer &#40;four hours is recommended&#41; to get rid of hard-shelled cryptosporidium cysts. These drops are definitely our favorite chemical treatment for backcountry water due to their packable design and ease of use &mdash; just make sure you have time to wait for your sterilization. The Aquamira Treatment Drops offer a great value for a couple of trips into the backcountry, but if longer-term value is what you're seeking, one of the other systems in our review may be a better fit, though it will mean a higher up-front cost. 
Read more: Aquamira Water Treatment Drops review

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