Bottle water filters vs. gravity filters

My experience is only with the Frontier Pro as part of a gravity system. However here is my take:

1. The Sport would reduce the capacity of the water bottle significantly – that could be a problem.

2. The Sport also has the same (nearly so) purification claims of the Pro, so I imagine the need for chemicals would be the same for the Sport as the Pro. The chemicals that people use are for the bacteria that the filter can't remove.

Like most things you have to figure out what will work best for you. I like the Frontier Pro because I see it as part of a system that I can tailor to my needs in any given situation.
I also like the gravity system because I can set it and go do something else while it works.

Sorry I really can't be of more help.

Mark:

Two things…

First, as above, the FP filter pore size is too big to screen out bacteria — and is thus a toy IMO. I believe the Sport is the same thing. I use FP actually, but I always pair it with chlorine.

Second, I would look for a filter with a nipple at both input and output — like the FP, but also the Sawyer filter (click here and here). Why? Because that allows the filter to be used any number of ways — including inline, in bottle, and gravity fed!

Note that the filters in both are exactly the same — just that one is sold as inline and the other is sold with a bottle. Unlike the FP, this is a real filter that can screen out bacteria and protozoa (but not viruses which are supposed to be uncommon out in the wilds).

The above references Sawyer filter — not Sawyer purifier.

Benjamin, I notice that you continually express concern about treating water for bacteria. Maybe where you operate there is such a problem.

I operate almost exclusively in the Sierra Nevada, and there sure isn't much in the way of bacteria in the water. Almost the entire risk is in Giardia lamblia, and the only people around me who have gotten sick from water have fallen victim to Giardia (water intake while swimming).

I think it is wise to understand the water risks in your particular area before you go treating it for something that isn't there.

–B.G.–

Thanks Benjamin – I've read your other posts on the FPro, and was almost sold on that system, but I thought I'd check out the in-bottle systems as a bare-bones alternative.

The Sawyers look good. I like the flexibility of having a filter than can be adapted to in-bottle or gravity fed use, although in their maintenance pdf it does seem to pretty much fill the entire bottle!

http://www.sawyerproducts.com/research/Sawyer_bacteriall_Bottle_Directions_SP149_05-25-06.pdf

I guess my point is that I'm not sure why I would really need a gravity feed system if I have filtered water I can just drink from a bottle. Not having it cuts out the need to carry and fiddle around with tubing and extra platys.

Bob:
I'm in Minnesota. Lots of available water. Lots of beavers enjoying it. I need a filter, and ideally one which doesn't get gunked up, is easily cleanable, and/or is cheap enough to be replaced.

Do you like to drink anything added to your water like powdered mixes? If you do, I don't think bottle filters will work with powders. Just something to think about.

David:
Good point. I do occasionally like to use a nuun or two.

Is it possible to squirt water through the bottle filters? I could fill a cup, add a nuun.

Aquamira do seem to be very clear that the Sport filters >99.9%, while the Pro filters 'only' 99.9% – so it's odd they call it the Pro.

Mark wrote, "I guess my point is that I'm not sure why I would really need a gravity feed system if I have filtered water I can just drink from a bottle. Not having it cuts out the need to carry and fiddle around with tubing and extra platys".

That's one of the reasons why I like the FP. You can screw the filter directly onto a Platy bottle (or std. size narrow mouth supermarket water bottle) and suck the water through the FP's built-in bite valve!

When hiking, I still prefer "hands free" drinking so I set up my FP as follows:

Platy bottle/bladder –> tubing –> FP filter at the end (drinking through the bite valve)

But at camp, I disconnect the FP and just screw it directly onto my platy bottle/bladder.

Well decision made – I went for the Frontier Pro.

I emailed Aquamira and got this reply from John Gustave:

"Our filters aren't actually rated by pore size. They rather have a Giardia
and Cryptosporidium removal rating. We have an article on our website
titled "a word about filter ratings", check it out. Per the comparison of the two, they are exactly the same. Our filters do not remove bacteria or virus, which are too small. We do recommend using our water treatment in conjunction with the filters to address those issues. I believe this is what you were referring to."

I went with the FP in the end, plus a platypus bladder and a soft bottle.

I'll grab some tabs also, but just out of interest, are viruses/bacteria a big problem in the States?

Thanks for all your collective help and comments!

Viruses, not so much. Protozoa, yes.

IMO, a "filter" that can only filter out the bigger stuff (protozoa) but not bacteria is worthless! Why? Thinking about it…

Any pool of water "rich" enough to sustain relatively big/complicated life forms like protozoa will obviously be rich enough to also support simple and tiny life forms (e.g. one-cell bacteria). I defy anyone to identify any pool of water that sustains only complicated life forms but not simpler ones!!

FP's statement about relying on another filter sounds logical in theory, but nonsensical in practice. If you were to carry a more sophisticated filter — then why the heck would you need the FP? As a super duper fancy pre-filter?? I don't think so.

Using the FP alone provides nothing more than a false sense of security. Pairing it with another filter is idiotic IMO. Pairing it with chlorine, however, can make sense.

Finally, AquaMira or Micropur chlorine dioxide tabs are expensive! If you've got the FP to trap the bigger (and harder to kill) stuff — then all you need is a few drops of chlorine to kill the tiny (and easy to kill) baddies! If using FP, don't waste your money on chlorine dioxide tabs! Just use chlorine (5 drops per quart or liter and let stand for 30 minutes) — then drink water through the FP filter to remove protozoa, particulates, as well as any residual chemical taste.

A protozoan such as Giardia lamblia can exist in virtually any water that is downstream from where any mammal lives or defecates, regardless of whether the water supports other life forms. Once the organism is in the water, it can exist in one of two forms, either the adult form, which is a large bug (maybe 35 microns) or in the egg/cyst form, which is a small bug (maybe 2-3 microns). The large bug can be filtered by many crude filters, but the egg form takes a slightly better filter. In the Sierra Nevada range, the risk is unpredictable. The kill temperature for Giardia is 175 F, so heating water for cooking will have devitalized the bugs.

In some tropical countries, you can have many more bacterial water problems. Part of that is because the water temperature is warm and bacteria can live easier. There are some nasty bacterial water problems that must be avoided at all costs.

In many third-world countries, waste water santitation is non-existant. As a result, downstream water must be assumed to have viral problems of all sorts, such as hepatitis. By the same token, it would be rare to have viral contamination of the water if you were well above all civilization.

So, again, consider where you are located, and consider the risks of the water that you will find.

–B.G.–

So the ideal, then, would be a Sawyer filter?

Mark,

The Sawyer Filter, which I have used for myself and my family for about 2.5 years now, is very effective for screening out everything except for viruses. (They have a filter that does that, but might not be practical to use in the field).

The only negative is that the Sawyer filter does not have an active charcoal element in it that can help with improving the taste of the water and for removing chemical contaminents.

For the Sierras, I don't consider this an issue.

Great system, pretty easy to use, but not perfect.

There are two very detailed reviews of the Sawyer Filter in the User Review section of the BPL site.

Hope this helps.

-Tony