Have been using Zero filters since 2013.  They work great, water tastes great, but since Hurricane IRMA, the filters are only lasting 1/3 as long as normal. We had several warnings advising not using the water without boiling first due to water main breaks.  We went to bottled water during that time period.  After the alerts were lifted I replaced the Zero filter, just in case, along with shower filters, but only 2 weeks later the Zero needed another replacement.  I'm guessing it was the water quality after the shut down due to water main breaks during the storm.  I replaced the filter for the 3rd time, and when an off taste started again two weeks later, I replaced it with the 4th filter. So far so good!  Thank you.