Probably not. A weak solution of chlorine bleach followed by copious washings with water should do the trick.

By the way, since it was Christmas Eve and nobody wanted to get too involved in anything related to work science, my colleagues and I spent the day yesterday speculating about this problem (many of us are very outdoorsy because we live in Colorado...it's just another room with a spectacular view) and we've come up with a hypothesis of what is happening. We don't think it's related to any kind of calcium build up, considering that my filter never came with in 50 miles of a calcium source. This is some educated guessing and some wild speculation but here goes.

We suspect that the fibers in the filter are a cellulose ester that, once wetted and then dried, stick together and clog the hollow fiber. The reduced flow isn't because of calcium salt build up but because the tube is restricted. The fibers don't swell upon wetting with water, hence the continued lack of flow even when wet again. Flowing acid through the filter doesn't remove the calcium but swells the fiber and breaks down whatever chemistry that is going on to close the fiber.

Cellulose ester is a plastic made from cellulose. The most common example, and the highest usage, is filter tow for cigarettes but it is also used in making film stock...you know the stuff we grandpas used before the damned digital camera I don't have a lot of experience with the actual cellulose ester but I do have lots of experience with making the cellulose that goes into making the ester and it can have some weird properties related to water content and where the paper was made. These properties may translate over to the cellulose ester and may even cause more problems for me here than for others in more humid climates.

Cellulose goes through a hysteresis of strength and other properties based on it's water content at the time of production. I'll use strength as an example but other properties follow this same trend. A paper made, and dried, in a high humidity environment like the southeast US or northwest US has a certain strength. If you take the paper to a dry environment like Colorado, the strength property goes down as the paper loses it's moisture. If you take it back to the humid environment, it gains back strength but not as much as it originally had...that's a hysteresis.

Now if you make the paper here in Colorado and let it dry, it has a similar strength but the moisture content is lower. Take that paper to a humid environment and it goes through a similar hysteresis but the strength lost is less and redrying the paper results in a lower strength loss in the end. We should make paper here in Colorado but we don't have the trees nor the water for the process and the end product is too cheap to make enough money by shipping the trees here.

I believe that the problems I had with my filter are related to a similar hysteresis that is related to the difference in regional humidity. Our absolute humidity in Colorado is much lower than the absolute humidity elsewhere in the US. Our thinner air means the air can't carry as much water. Our relative humidity is also lower because we don't get as much rain on the lee side of the Rockies. Both of these conspire to dry out my filter more than places like Maryland or the Midwest. When I air dry cellulose, I end up with a moisture content of from 4% to 7% depending on the time of year (winter is drier). People in the eastern and northwest US have moisture contents double to triple the highest moisture levels I measure...closer to 12 to nearly 20%. When they "dry" their cellulose or their water filter, they have a higher water content which keeps the tubes from collapsing. When I "dry" my filter it really does dry out and the tubes pinch closed.

It makes sense that staehpj1 could use his filter forever without every experiencing a problem and that I would experience a complete failure after one use. I think the only way that I could keep my filter operational is to never let it dry out. That opens the door to biological issues which I'd rather not deal with.