Aquatabs are chemical water purification tablets that help neutralize viruses, bacteria, and Giardia cysts in backcountry water sources. Their active ingredient is a form of chlorine that will purify clear, non-turbid water in 30-40 minutes. While you can use them on their own in certain circumstances, they’re best used in conjunction with a water filter that can remove parasites that Aquatabs can’t kill.
With a shelf life of 4 years, Aquatabs are tiny pill-sized tablets that come in individually wrapped packets that you can open by hand without scissors. Each pill can purify 0.75 liters of contaminated water. Great. But if you stop and think about it for a moment, there aren’t a lot of bottles used by hikers that are 750 ml in size. Nalgene bottles are 1 liter, most soda bottles are 1 liter in size, most soft bottles are 1 or 2 liters in size, and hydration reservoirs are also usually 2-3 liters in size. Packaging pills to only purify 0.75 liters doesn’t seem like a very friendly packaging size for outdoor recreation.
The Aquatab tablets are also tiny, making them very hard to divvy up into partial portions. Here they are shown side-by-side with Portable Aqua Chlorine Dioxide Water Purification Tablets, which are easier to cut into pieces if you want to purify part of a liter because they’re so much larger.
Then there’s the issue of Cryptosporidium. Cryptosporidium is a microscopic parasite that causes cryptosporidiosis, a disease that causes watery diarrhea. The parasite is protected by an outer shell that allows it to survive outside the body for long periods of time and makes it very tolerant of disinfection. While this parasite can be spread in several different ways, drinking water, and recreational water that have been contaminated with the feces from infected humans or animals, is the most common. According to the CDC, backpackers, and hikers who drink untreated backcountry water are at an elevated risk of contracting cryptosporidiosis. In the United States, an estimated 748,000 cases of cryptosporidiosis occur each year.
Comparable Chemical Water Purification Products
|Potable Aqua Iodine Tablets||Iodine||Yes||Yes||No||No|
|Potable Aqua Iodine and PA+ Plus Tablets||Iodine||Yes||Yes||No||No|
|Polar Pure Iodine Crystals||Iodine||Yes||Yes||No||No|
|Potable Aqua CIO2 Tablets||Chlorine Dioxide||Yes||Yes||Yes||Yes|
|Katdyn Micropur Tablets||Chlorine Dioxide||Yes||Yes||Yes||Yes|
|Aquamira CIO2 Liquid||Chlorine Dioxide||Yes||Yes||Yes||Yes|
While Aquatabs are effective at neutralizing viruses, bacteria, and Giardia, they are not effective against Cryptosporidium. That’s because Aquatabs are not chlorine dioxide tablets, but contain another substance that’s less potent called sodium dichloroisocyanurate. That surprised me because I just assumed Aquatabs were chlorine dioxide tablets. That’s before I dug into the details and started reading labels.
Aquatabs are still a good chemical water purification solution for purifying clear water and killing bacteria and viruses but in conjunction with a water filter that can first remove larger particles and parasites like Cryptosporidium and Giardia. But as a standalone solution or backup, Aquatabs are not as comprehensive as using chlorine dioxide water purification tablets like Katadyn Micropur or Potable Aqua Chlorine Dioxide Tablets, or Aquamira Water Purification Drops. While Cryptosporidium is not present in all backcountry water sources, if your filter breaks or clogs, it is prudent to have a backup purification method like chlorine dioxide that offers complete coverage, not partial.
The author purchased Aquatabs.SectionHiker is reader-supported. We independently research, test, and rate the best products. We only make money if you purchase a product through our affiliate links. Help us continue to test and write unsponsored and independent gear reviews, beginner FAQs, and free hiking guides.
Since AFAIK Aquatabs makes no claim to meet or exceed the EPA standards for microbiological water purification, I am surprised that they can claim their product is a “water purification” product.
Yes most water sources in the backcountry are not contaminated and, if crypto is present, it takes longer to kill than giardia with an EPA rated chlorine dioxide product. But it seems to me if you think you need to purify water, get the product with that kills the most critters like Katydyn Micropur. Or as you recommend, use Aquatabs in conjunction with a filter.
I suspect that the threshold for calling yourself a “purification” product rests on your ability to kill viruses, not crypto.
Any company can claim water purification (at least in the US) if the product does something to purify the water of something at any amount, since there is no US federal regulation on what a purifier product (filter or chemical) must do or purfiy against. There are EPA limits on contaminants for drinking water, but that is not the same as a chemical or filter purification product you are using to treat water yourself. There are voluntary protocols and standards like NSF/ANSI, but they are not mandated and those are protocols and standards on integrity of an item such as ability to filter x number of 9s or chemical safe for human consumption, they are not standards for what a chemical or filter product must do to be considered a purifier.
You can claim it, but you can also be sued for false advertising which is why smart consumers ask to see the results of EPA and NFS/ANSI standards when purchasing products and buy products from well known companies that make it a point to test their products and publish their efficacy rates.
So, which is the best? I hope there should be more detailed review about this.
Skip Aquatabs and buy Aquamira or Katadyn Micropur. They’re essentially identical, but Aquamira is also available in a liquid form which works slightly faster. I say as much in this article.
If you’re like most hikers that use Aquamira or Micropur and not waiting four hours to kill the Cryptospirium, then you might as well be using Aquatabs. Much lighter than Aquamira, although Aquamira has the neglible benefit of letting you drink your water ten minutes quicker. Maybe Micropur is the best option as you will have the protection should you ever need it, though it comes at a cost over the Aquatabs and I don’t know that you would ever encounter a situation where you would actually know that you need it (posted sign? Guthook comment?)
To me the real question is which is more prevalent (would be interested in greater U.S.), viruses, which the filters can’t remove, or cryptospirium, which the chemical treatments either can’t or won’t (due to user negligence) kill? Only then could you know which is the safest product to use (assuming not doing any multiple treatment to ensure all impurities are filterer/killed).