We have a 10L black Dromedary bag and I was reading up on some past gravity filter systems. I was reading where a Sawyer or MSR (or both?) would hook directly to the cap on this water bag? I looked online and our cap didn't look like the one listed in the old post.

What should I get for a reliable, flush-able filter that I can use for 2 to 5 people? And it looks like I can DIY it using our Dromedary and other collapsible water bags and some tubing and a filter, is that correct? A

I have an MSR Gravity water filter and the end cap that come with it will fit directly on the MSR dromedary bag or the Dromlite bags too. It screws right on to it. The cap on the bag itself can't be used with out some sort of other adapter as you would have to unscrew the little flip top on it and screw a small fitting on there. I'm not sure if someone has figured out some way to rig it up using a different type of filter set up.

Thanks, so you take the entire large cap off the bag and it adapts to those threads? Or you leave the main cap on the bag and unscrew the little flip top and use those threads? Sorry for the rookie questions, we've always used Steripens and tablets as backup but debating other options.

This is what my MSR Gravity system came with; it should be all you need.

Yep, what boonie linked is what I use for my custom system using the MSR Drom bag. I the photo below, you'll see that I have that piece with a short bit of blue tubing and a quick-connect. You'll see that I use a pricey 0.02 micron filter from Sawyer's sink purifier combined with a carbon canister, but you can just as easily do exactly what I've done but using a Sawyer Mini instead if you want to save $ and weight.

mschi772: "I wasn't happy with any premade gravity system, so I built my own using:

Kent Systems Acrolene tubing and quick couplings (1/4")
Sawyer filter from the purifier bucket kit (0.02 micron)
Katadyn activated carbon filter (bottle adapter)
MSR dromedary bags for filtered water (10 liter)
12 liter collapsible bucket for dirty water


I did not cut a hole in the bucket; I just run the line over the edge of the bucket and use my syringe (or, honestly, my mouth) to suck on the CLEAN side of the filter to start the flow. It takes no time to filter 10 liters. The bucket fills quickly compared to systems that use enclosed bags for dirty water, and it can be used for so much more; I store the whole system in the bucket (after rinsing the bucket with clean water) when packed. The whole thing disassembles into pieces quickly due to the quick couplings, and I even have some coupling plugs to put on each end of the filter to keep it from leaking when I pack it up between sites. The adapter cap that attaches the hose directly to the dromedary bag is your standard "Nalgene thread," so this system will attach to just about anything.

Obviously it could be whatever capacity you prefer, and you could choose a lighter bucket/bag and use a Sawyer mini instead, but for my larger basecamping group I love the large capacity and durability of this. I LOVE these dromedary bags; they're so bombproof! Shout-out to Kent's tubing for its insane durability, too--this Acrolene stuff is crazy tough.

It's plenty light for me, and if I need to shave weight, I use my Sawyer mini, leave the charcoal part at home, and switch to a smaller silnylon bucket and a smaller clean bag or just no clean bag and tap the system for water as needed.

The charcoal filter is unnecessary, but the girlfriend is very picky about water, so I added it so that any strange colors or tastes would not have to be an issue for her, and I have to admit that water from this system is amazing, and that charcoal filter does deserve some of the credit.

I am considering cutting a hole in a bucket and adding one of Kent's shut-off bulkheads (only flows when connected to another coupling) to it so that it can still function as a bucket but siphon-starting would be a thing of the past.

The photo below is the best I've got of the system in action, but it was taken when a friend attached their camelback to fill it instead.


Kent Systems
MSR Adapter for tubing to the bag
MSR Dromedary bag
Sawyer filter
Katadyn carbon cartridge
Bucket
"

cyclones30: "Thanks, so you take the entire large cap off the bag and it adapts to those threads? Or you leave the main cap on the bag and unscrew the little flip top and use those threads? Sorry for the rookie questions, we've always used Steripens and tablets as backup but debating other options. "

Yes you take the whole large cap off the Dromedary bag and screw the black cap with the hose nipple that cane with the filter.

What I did before they came out with that new cap is use this cap. Regular clear hardware store hose fits snugly into the spout and when filled, you just shut the valve and hang the bag to fill your water bottles.