SteriPEN Pre-Filter/Water Bottles That Work

it takes a little practice, but disposable coffee filters work great as a pre-filter. its lighter and much cheaper.

Wow I just over shot that landing. I was trying to lighten up my system and went tech instead of simple (K.I.S.S.). Thank you for that. I now have a few questions.

1. About how many "filterings" (is that a word?) do you get out of 1 coffee filter.
2. Do you attach it to the bottle with a rubber band? Or is there a better way?
3. What makes this method tricky? Are there little tricks I should know about?
4. Do you dry the filter out between uses?

Option 1 – Paper coffee filters are slow; use metallic ones instead — something like this:

Option 2 – Get a Steripen “fits all” filter instead.

Option 3 – Switch to Nalgene wide-mouth bottles — Steripen’s website mentioned them specfically:

http://dudadiesel.com/choose_item.php?id=fbp81

Take a wire cutter and cut and with pliers remove the steel ring, it brings the 1 micron filter down to about 1 oz.

It makes a tremendously fast pre-filter at about $2-$3 per bag depending on quantity you buy. They’re so cheap after a long hike, you can throw one away and start the next long hike with a new one.

We used one on the JMT last year and also on the Superior Hiking Trail. It worked fantastic on both, most especially the extremely silty, dirty superior hiking trail pond water. Pre-filtering went extremely fast, and afterwards, the normal sawyer filter fitted into a gravity filter system worked very fast. The final water was treated with Micropur tablets and we only had to wait 20 minutes before drinking. The whole system was under 3 oz weight (pre-filter, sawyer filter, antigravitygear gravity filter setup (we swapped the sawyer filter for their filter which we did not like).

Roleigh:

Can you tell us the flow rate (say for 1 quart or liter) and is this something available in most all auto stores?

The flow-rate is as if the filter was not there. There is no slow down, even with silty, filthy water. It is only 1 micron (not .1 micron). You definitely want to this as a pre-filter. On the JMT, using this with tablets is sufficient. On the Superior Hiking Trail, you'd follow up with a Sawyer filter/gravity water filter or pump filter system. (And for viruses, with tablets or bleach.)

I've only gotten this direct from dudadiesel.com either from their web site or from their ebay sell pages (but they say you get best prices from their web page direct).

Here are the links for the Sawyer Water Filter

http://www.sawyerproducts.com/SP121.htm

Weight: 1.8 ounces

This is a .1 Micron filter — best to use after pre-filtering with the 1 micron oil filter otherwise this can “gum up”, especially with the water on the Superior Hiking Trail. No need for this on the JMT — just the pre-filter and tablets is sufficient.

Here is the link for the AntiGravityGear water bag.

http://www.antigravitygear.com/proddetail.php?prod=AGWTBG

# Capacity: 1 Gallon
# Weight: 0.6 oz/18 g
# Material: 1.1 oz sil-nylon

You need some hosing and adapters – see later postings below by me with links to the USPlastic.com part numbers, and links.

AntiGravityGear used to sell the complete system with an AquaMira cheap filter that worked terribly for me, but I used their setup and just swapped in the Sawyer filter.

Thanks, Roleigh.

Up to now, I've been using a piece of metallic coffee filter — which filters out all visible gunk. I remember it as being 50.0 microns or thereabouts. A 1-micron prefilter that doesn't slow down water flow sounds like a great alternative.

I have not found the posting giving US PLastics parts to order but did find 2 interesting links.

http://preview.tinyurl.com/yzkures

http://preview.tinyurl.com/yjvy8rj

Still looking for that link.

I found the USPlastic.com order where I ordered the parts from the posting on BPL. Here is a picture of the order detailing part numbers and prices.

ps. I found the link using the part number for the search term, and this is the TinyURL for the BPL thread:

http://preview.tinyurl.com/yllmrjr

PPS. It was Tony Fleming who did original posting of the USPlastic.com part numbers.

Thanks you. I would have never looked at Bio-diesel filter. I just ordered ten of them. One of these with Aquamira in BPL Mini bottles will put my system at 2oz. Sweet.

You're welcome. I should mention, I used the pre-filter on the JMT with a Steripen during the day and at night, being too lazy and wanting to do about 6 liters quickly, I just used Micropur tablets.

For a pre-filter with my steripen I use the O.D. Dripper coffee filter from Montbell (.18 oz). I use a cutt off water bladder to scoop up untreated water. I then treat the water with the steripen and then dump the water through the O.D filter into my water bladder. The entire filtering and cut down water badder weigh in at 1.2 ounces.

http://www.montbell.us/products/disp.php?cat_id=52&p_id=1124538

Justin:

i use the brown disposable ones. they work well for wide mouth nalgines, and work best when you just seal them against the rim with your hand. you also need to have some falling water to make them work well, so i fill up at small waterfalls. however reuseable metal filters i think could be easier since they would fill the bottle faster.

to make it easier, make sure the filter isn't tight and it dips a little into the bottle in the middle. a few minutes of practice at home should help you figure it out.

I just bring a dozen or so filters, and throw them into my trash bag after using them to fill up the two naglines i keep with me. i could dry them and reuse them, but i don't think that would be worth the effort.

Roleigh,

I was just re-reading about your gravity filter, and your comments on the DudaDiesel bag for a pre-filter.

I wonder — what if you took a DudaDiesel bag and put it over the barb on the inside of your dirty bag. You could seal the open end of the bag between the male and female adapters. This would give you a built-in pre-filter, which should be very convenient.

Would this work?

— MV

I've been eying the GSI cloth style coffee filter (http://www.rei.com/product/784659). Most of my hiking is in areas with fast running streams so water clarity is rarely an issue. I've *assumed* that a bandana would get me through if needed– just not as neat and easy.

Dale,

I like metallic mesh filters. Won’t retain water and dries instantly — unlike paper or cloth filters.

I’m sure you’ve seen my light and compact “water scoop with prefilter”?

On