Product review (3 stars): Good filter, but not great.
Although this filter did a great job of keeping our home well-humidified, I wish that they would last a little bit longer. The quality of our water is obviously a contributing factor, but it seems like these filters only last about two weeks before they become completely hardened by calcium and other mineral deposits. We have been able to extend the life of the filter by soaking them in vinegar every week or two to dissolve the accumulated minerals, but the filters begin to degrade after one or two vinegar bath cycles. Without the vinegar bath, they become very hard and the humidity output drops significantly. Given that our water is not exceptionally hard nor soft (standard city water), I was disappointed that these filters last such a short time without the vinegar baths. Overall, I would rate this as an average filter, not exceptional but not bad either.