Originally Posted by cyccommute

"Inspecting" is different from "testing". There is no way to determine if the Sawyer filter is malfunctioning by "inspecting" it. Even if that I would have known about the calcium buildup issue simply "inspecting" the filter wouldn't have told me if I had the problem or not. Even if I had "tested" the filter (without prior knowledge of the calcium buildup problem), dried it out and put it back in the bag, I could have caused the same problem because it happens when the filter dries out. I did "inspect" the filter to determine that all the parts I needed would be there. This is a not an issue that occurs all the time but it is known to Sawyer and a heads up in the instructions would have been in order.



I don't "test" stuff following storage because I don't put away broken equipment. If something is broken, worn or needs replacement at the end of a tour, I fix it, mend it or replace it. I'm make sure that I'm familiar with the operation of a new piece of equipment before I go using it on a tour but this filter was not something new. I had used it before hand and it worked well. Since the filter was in good order before it went into storage and since I had no reason to expect that the filter wouldn't come out of storage in the same order it went into storage, there was no reason for me to not expect it to work in the same manner as it went into storage.

A further issue which will keep me from trusting hollow filters like the Sawyer again is that I live in a state where water evaporates quickly. I have no idea how long it would take for the calcium clogging issue to happen nor the parameters needed to make it happen but I'm not prone to leaving my water filtering equipment wet for extended periods. The whole biofilm discussion above has some merit. The best way to avoid build up of that biofilm is to not give it the conditions for it to happen. That means drying out water filtering equipment. If a Sawyer filter can clog on drying and need an acidic flush to re-establish a fraction of the flow (it doesn't all come back), I wouldn't want to depend on it for something a critical as water.



Again, this is not something that anyone would reasonably expect. The filter came to me dry. I used the filter a single time and filtered clear water from a clear stream at 11,000 feet where there is zero mineral load. I was less than a mile from the headwaters of the stream and the stream flows over Colorado granite which is composed of feldspar and quartz...to minerals that have a very low solubility in water. I dried the filter prior to storage and had no reason to expect that it would be clogged with anything. I've used hollow filters before at work and they will go for years and years before even slowing down. There is simply no reason to expect the filter would fail after a single use.

To use a bicycle analogy, this is akin to putting brand new cables on a bike and not using it for a couple of months only to find that the cables had dissolved. It's not an expected, or even conceivable, problem.