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We're going on a hike with 8 people,and we were wondering if a gravity filter is a good addition to our pumps.A few questions though.Do they purify as well as pumps?And are they worth their weight?
lutefisk
02-08-2011, 11:43
I usually have groups out about 6 weeks each year and I've been using a gravity filter as our primary for the past 2 years. The Platypus filter is 0.2 microns and the Sawyer is 0.1 microns, comparable to pump filters. As with all filters it helps if you pre-filter whenever there is a lot of sediment and debris in the water source. You can backflush the filter as needed during the trip to keep it flowing fast. Also, never let your filter freeze. They are fast and the weight isn't bad, especially considering the volume of water you can filter with little effort. As always, have a back-up plan - Aquamira, bleach, iodine, or whatever.
We are hiking with the Platypus Gravityworks for varying reasons. If you get rid of the good water bag (we are since we are carrying Big Zip bladders) then you shave 5 oz off the package. The 4 L bag, with inline filter weighs in at 7 oz then.
Whats cool is the ability to purchase a few accessories and have the in line filter flow directly into your bladder without even taking it out of your pack.
couscous
02-08-2011, 13:36
I carry a Platypus Clean Stream Gravity Filter when hiking with the scouts. Easy way to filter gallons of water for a group.
We are hiking with the Platypus Gravityworks for varying reasons. If you get rid of the good water bag (we are since we are carrying Big Zip bladders) then you shave 5 oz off the package. The 4 L bag, with inline filter weighs in at 7 oz then.
Whats cool is the ability to purchase a few accessories and have the in line filter flow directly into your bladder without even taking it out of your pack.
One of the water bags weighs 5oz? I'm thinking of getting one of these for my thru hike instead of the Katahdyn hiker pro. Do you think you could use a gatorade bottle instead of the bladder? And how hard is it to clean this filter?
Whats a good way to pre filter it?
envirodiver
02-08-2011, 16:34
We're going on a hike with 8 people,and we were wondering if a gravity filter is a good addition to our pumps.A few questions though.Do they purify as well as pumps?And are they worth their weight?
Not to nitpick, but filters (with the exception of the First Need Filter) are not considered to be purifiers. The only purifier is the Sweetwater system that utilizes chlorine dioxide drops after filtration. Purifiers also by definition remove viruses and filters do not remove organisims that small. Chemiccal systems are purifiers.
However, the quality filters do remove bacteria and cysts which is our , main concern.
I have a gravity filter that I use every now and then. It's a bit heavy, but for larger groups isn't bad.
Whats a good way to pre filter it?
Bandana or coffee filter
envirodiver
02-08-2011, 16:38
Whats a good way to pre filter it?
Can be as simple as pouring the water through a bandana or coffee filter if it is suspended solids. You can also dip out of the stream with a cook pot (the pot will be disinfected when you boil water in it for a meal , tea, etc.) to pour into the filter. If you dip with care you won't stir up the mud, sand, etc. on the bottom and the water will stay clear.
We've used coffee filters in the past with actual pumps,but for a gravity filter,whats the best way?We're only carrying JetBoils.Is water in Southern Virginia that bad?Should we even worry about pre-filtering?
Luddite and crew,
The details and specs can be seen here: http://cascadedesigns.com/platypus/filtration-and-storage/gravityworks-filter/product
We are doing a section with 5 total, and I am needing a solution for my wife and I for sure. The total package is 11 oz. Basically 5 oz per bag, and 2 oz for the filter. You can take the second 5 oz bag off making a 7 oz total system that will feed water in to whatever source you want!
I purchased a quick connect accessory that splices clean into the drinking hose on a big zip. The idea is to hang the bag, plug it into the bladder hose and let gravity do the work. Then I wont have to pull the bladder from my over stuffed bag. I'll see how it works here shortly.
Regardless, for the right application, 7 oz system that will do 1.75 L per minute isnt too bad. Check it out.
OK,but is there enough sediment in the water to even have to worry about pre filtering?
gipcgirl
02-08-2011, 18:10
We're going on a hike with 8 people,and we were wondering if a gravity filter is a good addition to our pumps.A few questions though.Do they purify as well as pumps?And are they worth their weight?
I used a platypus filter on my thru last year, it was great no problems easy to use. Most importantly I never got sick not once.
Luddite and crew,
The details and specs can be seen here: http://cascadedesigns.com/platypus/filtration-and-storage/gravityworks-filter/product
We are doing a section with 5 total, and I am needing a solution for my wife and I for sure. The total package is 11 oz. Basically 5 oz per bag, and 2 oz for the filter. You can take the second 5 oz bag off making a 7 oz total system that will feed water in to whatever source you want!
I purchased a quick connect accessory that splices clean into the drinking hose on a big zip. The idea is to hang the bag, plug it into the bladder hose and let gravity do the work. Then I wont have to pull the bladder from my over stuffed bag. I'll see how it works here shortly.
Regardless, for the right application, 7 oz system that will do 1.75 L per minute isnt too bad. Check it out.
Does it filter as good as the Katahdyn Hiker Pro?