I have the sawyer gravity filer system with two bags. I have used it for approximately five years and always backflush with the sink adapter after every trip. On my last trip the flow was good but it gave the water a horrible swampy/moldy taste. I know for sure the filter was the problem because my buddy had a pump filter with that made the water tasteless. To confirm I ran the pumped water through my gravity filter to my bottle and the awful taste came back again.

I am guessing something grew in there while it sat in my basement for the last year. Has this happened to anyone else? Is there a fix or am I buying a new one?

Sounds like there could have been some residual water left in the filter. After returning from a trip, I'll generally do a back flush and then run clean water through it. After that I'll let is set for maybe a week, uncapped, so that all water inside the filter has a chance to evaporate.

There are a couple of things you might try to save it. First I'd try a vinegar solution ... half vinegar/half water (at least a quart of total volume). Let that run thru your filter (set up in gravity mode). Let sit for at least a half hour and then run clean water through it.

If the taste remains, I'd use a Clorox solution ... 1 part Clorox/4 parts water. Then repeat the procedure above.

dd

You can try backflushing with some bleach several times to see if that takes care of the problem. If not pitch it.

After every trip I run a duluted mix of water and bleach through my filter. This kills anything that was growing in there.

quote Savage Voyageur: "After every trip I run a duluted mix of water and bleach through my filter. This kills anything that was growing in there. "

I do this, plus after a day or so of letting it 'air dry' I'll take it outside and fling loads more water out of it. Mine usually hangs vertically a good month after use before I wrap it up and put it away.

quote Savage Voyageur: "After every trip I run a duluted mix of water and bleach through my filter. This kills anything that was growing in there. "

Same here. And then hang the filter and let air dry for a month.

Maybe I'll try running a mild chlorine solution through mine. I figured that they would never dry out totally, and that funky things would start to grow, so I throw them away at the end of each season and just replace them.

I'd guess from what you're saying it is worth investing in a 2nd one as a back-up anyways. Better safe than sorry when it comes to filtering your water.

Thanks for the tips guys. I always backflush a ton of tap water through it and let everything hang dry after every trip but I guess I will hit it with the bleach from now on.

Hopefully the bleach can save it, if not I know where my REI dividend is going next spring!

+1

Yup, back flush, bleach solution, drain, fling in the yard AND bring a back-up on the trail.

What sort of bleach to water ratio do you use?

Sawyer recommends 1 cap of bleach per quart of water.

Sawyer Cleaning Instructions

To the OP, they also mention clogged filter being soaked in hot water then backflushed as well as calcium build up being soaked in vinegar.