Solutions for Self-Reliance

Potable Aqua Plus Water Purification Tablets Review


The Potable Aqua Plus water purification tablets is a two-part kit; purification tablets and neutralizing tablets to remove the distinct iodine taste and color from the purification tablets, and you’ll get enough 50 tablets of each so you’ll be able to purify 25 quarts or liters.

This kit makes water bacteriologically safe to drink and taste good, all in roughly 40 minutes, and is intended for short term and emergency use. Sure you could boil the water, but if you’re on the move or don’t have access to fuel then this is a convenient alternative to get safe drinking water.

Here’s the breakdown:

Performance – 6

There are two things about the Potable Aqua Plus that is worth to bring up; ability to purify water, and taste.


The active component in the purifying tablets is 20 milligrams of Tetraglycine Hydroperiodide (TGHP) which releases 8 milligrams (ppm) of titratable iodine as well as hypoiodous acid (HIO). Both are effective germicidal compounds, e.g. bacteria, viruses and many cysts such as giardia lamblia.

Iodine purifies the water by penetrating the cell wall of microorganisms and killing them, and here are a couple of the “bad guys” that these tablets kill:

  • E-coli
  • Salmonella
  • Cholera
  • Streptococcus faecalis
  • Infectous hepatitis
  • Giardia lamblia

Note that Potable Aqua is not effective against cryptosporidium cysts, so if you suspect your water is contaminated with cryptosporidium then boil the water as an extra precaution.

And neither does Potable Aqua neutralize or remove chemical contaminants or remove particles, so if you purify muddy water you’ll drink muddy water. Potable Aqua can be used with a basic or more advanced water filter though.

Another important note: If you have thyroid problems or are pregnant then you are advised to consult a physician before using iodine-based products. It “should” be safe, but you better make sure.

Iodine has some advantages over chlorine as a purification method. It’s less affected by organic matter in the water, it has better shelf life stability, plus it’s effective over a wider range of temperature and pH conditions.

Bottom line: The Potable Aqua Plus is a very decent purifying solution for short term emergency needs.

But it’s an imperfect solution because it does not protect you against cryptosporidium cysts and neither does it remove particles or chemical contaminants.


And now to the less pleasant aspect of using iodine to purify water…

Iodine adds a distinct “taste” and color to the water. Honestly I don’t think it’s that bad, but I’m sure that many people would disagree with me.

Here’s what clear tap water looks like after iodine purification (left) and then after the second step of adding neutralizing tablets (right):

Iodine purified water

Gladly the taste and color is no problem with the Potable Aqua Plus kit, because you get a bottle of PA Plus neutralizing tables that almost instantly remove both the iodine taste and the color, making it look and taste like regular water (although it does not remove particles so muddy water will still be muddy).

Construction Quality – 6

You get 50 purifying tablets and 50 neutralizing tablets, and they come in tiny sealed bottles with a screw cap.

As for the quality of the tablets themselves, there’s not much to say about them. Pharmacal, the company that produces Potable Aqua, has been producing them for over 50 years and they deliver straight to the U.S. military and other militaries around the world.

The purifying tablets contain 20 milligrams of Tetraglycine Hydroperiodide (TGHP) and they do what they’re supposed to do.

The neutralizing tablets (PA Plus) contain 45 milligrams of ascorbic acid (Vitamin C), and it takes away the taste and odor of the iodine by converting it to colorless and odorless iodide.

The PA Plus tablets disintegrate rapidly and will remove the iodine taste and color within three minutes (although I found they removed the color instantly when shaking the bottle).

Ease of Use – 6

These purification tablets are very easy to use. Add 2 tablets from the bottle with a white screw cap to a quart / liter of water, with the cap loosely screwed on to allow a small amount of leakage. Wait 5 minutes and shake the bottle to moisten the screw threads and then tighten the cap. Wait 30 minutes before drinking. That’s it.

Now, if you’ve got the water purification neutralizing tablets (with the yellow cap) that’s included in the Potable Aqua Plus kit, then the next step AFTER the 30 minutes is to add 2 of these tablets per quart or liter of water, shake well, wait 3 minutes, and now you have good tasting water without the iodine taste or color.

One neat feature that I appreciate is that they’ve color coded the bottles. White cap for purification and yellow cap for neutralization. Just make sure you don’t mix up the caps!

One hassle with this purification solution is that there’s waiting time involved. With a water filter you can just pick it up and drink from whatever water source you stumble over, but with the Potable Aqua tablets you have to wait roughly 40 minutes. Another hassle is that it’s impractical to purify large amounts of water at once.

Maintenance – 8

An unopened bottle of Potable Aqua tablets can be stored for four years without losing its effectiveness, as long as it’s stored in the proper conditions. A storage temperature between 60 and 86 °F (15 to 30 °C) is ideal.

To check the date of manufacture on your bottles, look for a 5-6 digit number printed vertically on the side. The first 1-2 digits represent the month of manufacture, the next two digits the year of manufacture, and the last two digits the batch number.

On mine it says 11421, meaning my tablets were produced in the 1st month of 2014 and is from batch number 21.

And keep in mind that any exposure to heat, humidity, moisture, and air will reduce the effectiveness of the tablets, and that’s why the manufacturer recommends an opened bottle should not be kept for more than a year.

Once you’ve opened the bottles just make sure you keep the caps screwed on tight in between use and they should last you a good while.

If in the field, check the tablets appearance to determine if they are still effective. If the tablets are gray or dark brown in color, they are still “likely” to be effective. If they are light green or yellow, it means they are “probably” no longer effective, meaning one can never be sure.

Brand Reputation – 7

As far as purification tablets go, Potable Aqua by Wisconsin Pharmacal has long been considered one of the best. They’ve got hundreds of positive reviews on Amazon

Potable Aqua was developed by Harvard University together with the U.S. Army in the 1940s for emergency drinking water disinfection in the field, and have been used worldwide by military, disaster relief organizations and campers ever since.

The company also sells Sting-Eze® Insect Bite Relief Products and BaitMate® Fish Attractants, and although I had not heard of those brands before they seem to be well regarded by those who have used them.

Guarantee – 4

There’s no expressed guarantee or manufacturers warranty on their website, but I’ve heard from people who have received very old bottles, (for example that expired 5+ years ago) with rusty screw caps and broken seals. In most cases they returned them to the retailer and got a new replacement without issues.

No guarantee or warranty information brings down the score a couple notches, but at less than ten bucks it’s probably not worth the time and effort anyway to return the bottles in the mail.

Sustainability – 5

These tablets have been manufactured since the 1940’s and have survived multiple crises in finance, oil, and the environment.

Even though the tablets were developed at Harvard University the production process itself is not rocket science. But regardless of how environmentally or financially sustainable the production process is I’d expect the Potable Aqua tablets to stick around for a long time, if only because it’s used by the military.

Self-Reliance – 3

Will this help you become more self-reliant?

Short-term, yes. Long-term (6+ weeks), no.

Potable Aqua is intended for short term emergency use only, up to a maximum of six weeks, because too much intake of iodine can mess with your thyroid function (it’s the same with any table salt that has added iodine).

The thing is that if you’re stationary and have access to fuel to start a fire (or an electric / gas oven), then boiling the water is a just as good solution for both long-term and short-term water needs.

I would not write off Potable Aqua though, because it can be a cheap and quick life saver during emergencies or brief camping trips when you don’t have time to prepare and start a fire, or when you are in an urban environment where you are dependent on electricity to boil water.

Just keep in mind that one bottle of Potable Aqua will only give you 25 quarts / liters of clean water, and if you drink 3 liters per day that’s only slightly more than one weeks worth of water. If you’re a family of four on the other hand one bottle of Potable Aqua will only last you two or three days at most.

Value – 2

You’ll find the Potable Aqua Plus package $7.99 on Amazon or $11 at REI, and for that price you’ll be able to purify 25 quartz / liters. That’s 32 cents per quart / liter, which is really expensive.

Compare that to the LifeStraw water filter where you’ll pay 2 cents per quart / liter at a price of $19.95 and a 1000 liter capacity.

The LifeStraw also removes particles which means you won’t be drinking muddy water.

And with the price per unit of purified water in mind I don’t think that the Potable Aqua is good value for the money. I’d rather spend another ten bucks to get the LifeStraw. It’s twice the price but has forty (40) times the capacity. Seems like a better deal to me.

Excitement – 2

I’d be thankful to have these bottles with me in case of emergency, but I’d be even more thankful to have a water filter with me. I’m all about long term solutions, and the short-term nature of Potable Aqua is not up my alley.


Contains: 50 purifying tablets and 50 neutralizing tablets
Active purifying ingredient: Tetraglycine Hydroperiodide (TGHP) which releases 8 milligrams (ppm) of titratable iodine
Active neutralizing ingredient: Ascorbic acid (Vitamin C)
Capacity: 25 quarts / liters

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