Monday, May 16, 2016

Why the Sawyer mini filter is my current favourite portable water filter

Readers who have read my posts would know that I am not a fan of residential drinking water filters for where I am staying now - Singapore. However, water filters can be necessary when:
  1. You are going to or currently staying in a less developed area of the world where
    1. there is no piped water
    2. Or the piped water is of questionable quality
  2. You want to prepare for emergency scenarios in which you are not expecting piped water to come out of the tap anymore.
  3. You want to engage in disaster relief i.e. an emergency scenario has already occurred somewhere else and you are heading there as a responder.
Under point number 1, I believe in carrying along a portable water filter whenever I am heading out into the wild, even somewhere as near as the jungles of neighbouring Malaysia. But through the years, I have also brought my water filter along even if I expect to be staying in hotel rooms. I guess that is the boy scout in me telling myself to be prepared. (Hey, it's true - I was a scout in my school days!)

For the past 10 years, this was my favourite portable water filter - the Katadyn Mini. It uses a ceramic core to remove bacteria and parasites and it is good for 7000 litres! Wow, that was a good deal of capacity in those days. Plus it small (relatively) size, few filters came close.
Figure: Katadyn Mini
Then technology happens...

It progresses so rapidly that sometimes we lose track of better products coming out in the market. I started hearing about the Sawyer Mini water filter for a year or two but didn't think much about it. After hearing a fair share of its good reviews, I decided to give it a try. Here's a comparison between the my old and new favourites.

Figure: top - Katadyn Mini, middle - Sawyer Mini

First thing you notice is the significantly smaller size of the Sawyer. At this size, it can be really handy to carry around. In fact, you are more likely to forget that it is there in your bag.

And if you read its specs, they look impressive. It has a capacity of 100 000 gallons (yes, that translates to roughly 380 000 litres!). If you are in survival mode and need only 2 litres of drinking water per day, this mini beastie will work for 500 years - virtually forever!

It is designed to filter down to 0.1 micron absolute. (In contrast, the Katadyn is rated down to 0.2 micron. Since they did not specify on the package that the rating is absolute, I believe it should be nominal.)  It is cited to remove 99.99999% of bacteria and 99.9999% protozoa.

The size and specs are no doubt wonderful but in my opinion, its unique selling point is its versatility in usage. You can use the water pouch (included) to store your raw water. Connect up your filter, squeeze and you get drinking water straight into your mouth.

And if for some reason, you lose the pouch, no worries, simply use the ubiquitous PET soda bottle to store your raw water. Attach the filter on top and you are good to go.
 And if you ever are desperate enough to be without the water pouch or a soda bottle, you can attach the straw provided and drink straight from the water body.
As an aside, the first water filter that allows the drinker to drink straight from the pond is, I believe, the LifeStraw. Widely publicised and distributed to developing countries, it was indeed a technological marvel. It was rated for 1000 L, 0.2 micron nominal, 99.9999% removal of bacteria and 99.9% removal of protozoan cysts. Incidentally, both and LifeStraw and the Sawyer filter make use of hollow fiber membranes, in contrast to a ceramic element in the Katadyn Mini.
Figure: Comparing the LifeStraw (above) and the Sawyer (below). Notice that the LifeStraw is only designed to be drank straight from the water source while the inlet and outlet nozzles of the Sawyer make it infinitely more versatile.
Best of all, it can be used as an inline filter, either sourcing from your own personal hydration pack or connected to a communal water tank.

Filters for Life Program – Worldwide

But before I go overboard on the Sawyer's strengths, do note that it is not rated to remove viruses. It also does not remove taste, odour and colour. (Therefore, it is possible for your filtered water to appear yellowish if your raw water is coloured to start with.) It has no activated carbon to remove these unsavoury stuff. And it definitely does not remove pesticides, heavy metals. Do not even try with seawater.

Though I mentioned its advantage as an inline filter, do not try fixing it to your water mains. The hollow fibres are rated to a maximum pressure of 60psi but the casing will actually burst at 40psi as a safeguard. Your mains may or may not exceed that pressure.

Finally, it is not certified under NSF/ANSI standard 42 or 53 which of course are designed more for residential water filters. Still, some water filter bottles are starting to get such certification.


Yes, the above image and several links in the text are Amazon Associate links. But I have to stress that no way will I recommend products that I myself do not believe in. More often than not, I have used them personally and am confident of their performance.

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