I finally got my hands on a Platypus CleanStream replacement cartridge to play with.

After making a very light (but not effective enough) gravity filter in THIS POST I decided that I would sacrifice a little weight for a more effective filter.

I just swapped out the Frontier Pro with the Platypus CleanStream filter.



Works the same way... just connect your drinking tube to it and let it go. So far so good.

Here's a quick comparison:



The Platypus filter has a hose nipple at either end. The blue covering is a rubber material similar to the orange stuff on
the Aquamira. The fins on both ends that protect the hose nipples are kinda "squishy".

They are about the same length, however the Aquamira filter would normally have the cap and bite valve
removed, making it a little shorter.

Platypus: 4.1oz rated at 1500 liters filters 99.9999% of bacteria and protozoa down to 0.2 microns flow rate 4 liters / 2.5 min
Aquamira: 2.2oz rated at 190 liters filters 99.9% giardia & cryptosporidium down to 3.0 microns flow rate unknown but slow

So this means it should fill the bottles WAY faster and you won't need to treat the water for bacteria, and should last MUCH longer.
Should bring entire gravity filter kit to about 5.5-6 oz which is still slightly less than my Katadyn mini, faster, and much less work.

In practice, the CleanStream seems to take about 5-6 min for a gallon. I still have a hose barb sticking up inside the water bag so that there is room for silt to settle. Also put one of the little fiber-fill type pre-filters from the Frontier Pro inside the hose barb fitting on the bag.

It weighs in at about 7oz wet and I shouldn't have to carry Aquamira to treat the water, but would carry a little as a backup until I get a chance for further testing.

Edited by Thangfish on 02/07/2009 10:18:36 MST.

There are serious viruses that even the 0.2 micron filter won't take out. The EPA recommended 2 drops of bleach per liter in your feeder bag will take care of the viruses and also retard growth of various flora in your filter. If you don't like the taste of chlorine, you can add yet another (charcoal) filter to your setup.

Thanks for posting the flow rate for the filter. I've been curious if the manufacturer's data were honest.

As far as I know, it's not possible to filter viruses with a commonly available consumer type filter.

Sawyer makes a 0.02 micron filter they claim will filter viruses. That's right, 0.02 micron not 0.2 micron.

It is fairly costly, (somewhere between $100 and $200) which is why I suggested you add the EPA recommended 2 drops of chlorine to your dirty water instead. It will kill the viruses so you don't need to use the expensive filter. You're platy filter will remove the things the chlorine doesn't kill effectively.

If you don't like the chlorine taste, you can get a cheap charcoal filter which you can install below your platy filter to remove the chlorine.

Edited by herman666 on 02/10/2009 11:23:40 MST.

Check into the known contaminants in your hiking area. Viruses are not known as problems in many areas.

Problems come and go. Unless there is an ongoing monitoring program, there's no way of knowing what's in the water.

If you elect to take the risk of drinking untreated water, fine. If you don't, what I previously recommended will significantly reduce your risk of getting sick.

I was under the impression the Frontier Pro contains charcoal. Is it a fact that the platy one does not?

Also as stated already, neither seem to be a 'one product solution'

Edited by Lyrrad on 02/11/2009 09:14:05 MST.

You are correct. The frontier pro contains charcoal, the platy does not. If the Pro had a smaller pored filter, it would be an excellent filter solution. Since it doesn't, I made up my filter from a Sawyer 0.1 micron filter followed by a Katadyn charcoal cartridge. Both purchased from REI.

Sawyer is guaranteeing their filter for life now by the way.

When I get home, I'll post a photo of my filter. It is very similar to the one that's the subject of this thread except of course, it has the additional charcoal filter.

Here's the promised photo of my filter setup. At 9.2 oz, it's a little heavy, but still quite a bit lighter than my miniworks which is a 0.2 micron filter with a charcoal after filter.

The setup shown uses a platypus 2 liter dirty water bag with a side exit that allows for heavier things like sediment to settle out. The black canister is the Sawyer 0.1 micron filter. The gray canister is a katadyn charcoal filter that removes chlorine and many other dissolved contaminants that get past mechanical filters.

I also installed a platypus inline valve after the charcoal filter and a fitting that lets me plug the filter directly into my nalgene hydration bladder.

This filter is slower than the miniworks, but I don't mind since I don't have to pump, I can tend to something else.

> Sawyer is guaranteeing their filter for life now by the way.

So what happens when it eventually clogs?
Do they replace it free??

1. So far as I know, you can backwash the filter to restore it.
2. I strongly suspect the in-line Sawyer filter is also "vulnerable" to the same risk of cold as the MSR Hyperflow...that is that the filter elements , if frozen, are permanently damaged and non-functional thereafter. Anyone have first-hand knowledge of this?

> > Sawyer is guaranteeing their filter for life now by the way.
> So what happens when it eventually clogs?
> Do they replace it free??

Maybe they declare that it has reached its end of life?

Cheers

The Sawyer filter, (and the platy, and most filters for that matter) will be damaged by freezing. Damage by freezing isn't covered by the warranty. I'd say if you're expecting cold temperatures, put your filter in a ziplock bag and carry it inside your jacket.

When the filter clogs, you backflush it.

These and other questions about the Sawyer filter are answered at www.sawyerproducts.com.

Edited by herman666 on 02/12/2009 09:15:02 MST.

Ok, I found it.

BTW, I tried very hard to research these filters and this company (they are only a distributor, I forget the manufacturer, but I posted it somewhere on here I think) a couple of years ago and found almost nothing... hadn't looked lately.

Anyway, it appears that these are indeed lifetime filters.

Along with the normal assurances for manufacturing flaws, they guarantee them for life (which I guess means the life of the company?).

From the Sawyer web site:

"All of the Sawyer® water filters and purifiers come with a MILLION GALLON GUARANTEE!"

Back flushing must be very efficient in this design (which appears to be the same technology as the Clean Stream and other MSR stuff).

I'm ordering one to test. Thanks for the heads up, Herman. How difficult is the back flushing, and is full flow restored?

Edited by Thangfish on 02/12/2009 17:44:51 MST.

>How difficult is the back flushing, and is full flow >restored?

Chris,

Sawyer sells an attachment for back-flushing from a faucet. As far as I can tell, flow is completely restored. I've never back-flushed on the trail, but I've never heard about any difficulty. Also, the water sources on my hikes are pretty clear. When I used the MSR MiniWorks filter, the element only needed cleaning about once a year.

Which filter did you order? The 0.1 or the 0.01 micron filter.

H

> Which filter did you order? The 0.1 or the 0.01 micron filter.

The .1

Hello:

I have a very similar set up on my platy : no pre-filter.

the attachment that comes with the filter works wonderfully.

only complaint I have is that the filter needs to be "primed" (for lack of a better word) before it flows well. It's pretty hard to suck water into the filter unless you already have water in the filter. Once you get some water in there it flows really well. I keep my hose dangling, and sip whenever I'm thirsty.

the filter rides on my Blast's shoulder strap.

I've been looking over a bunch of different posts about gravity filters lately, trying to decide which one to buy or build.

I purchased a frontier pro and some chlorine tablets, thinking I was going to go that route and then I saw this thread and learned about the sawyer and platypus filters, both of which filter to a much smaller size than the frontier pro can. Then I saw the sawyer 0.02 micron filter which can even filter viruses.

So that got me thinking. I'd like to find the ideal balance (for me) between minimizing weight and maintaining a high standard of filtration. I've been using a first need purifier (made by general ecology) for years with exceptional results. My only complaint has always been that it's a bit heavier than i would like (at about 16 oz.).

But a few moments ago I had an epiphany. The first need purifier has a gravity feed option. You're supposed to feed the dirty water through the pump still but you might be able to circumvent the pump and install the purifier cartridge inline. You may have to prime it somehow to begin the flow of water.

I'm not sure if it will work or what challenges might arise but I think I'm going to go home and try it. I believe the cartridges by themselves weigh about 5-6 oz. which would put it in the same ballpark as some of these other gravity filters but with the added benefit of it still being a chemical-free purifier.

If it works, i'll post some photos showing the end result. Of course, if any of you have already tried this, perhaps you can save me the wasted time...

"I believe the cartridges by themselves weigh about 5-6 oz. which would put it in the same ballpark as some of these other gravity filters but with the added benefit of it still being a chemical-free purifier."

Don't we wish! The First Need purifier core weighs 10 oz. dry -- and it's still fairly bulky. The First Need will do everything that a Sawyer can do -- plus improve water taste because it incorporates a carbon core that the Sawyer lacks. But the First Need requires quite a bit more sucking effort!

Due to its bulk and the sucking effort required, I opted to stick with my chlorine/Frontier Pro combo. YMMV.

Edited by ben2world on 03/30/2009 19:05:19 MDT.

Nick, the First Need filter will work as a gravity system. If you read the instruction pamphlet it shows how, but they have it go throw the pump. First Need

I just omitted the pump and hung the system and it works great- I went through the whole Bowron Lake circuit (70 mile canoe trip) using it that way and had no problems. I also used it this way for 10 years when I had time in camp to hang a bag. Of course all of this was before my light weight days
There are lighter weight systems out there but none will filter/purify better.
I don't use it any more because of the weight and high cost of new cartridges.

Edited by bestbuilder on 03/30/2009 19:23:43 MDT.