I have been using my since 2016 I think.  I was haing a problem with excema, and I heard womeone say that a water filter helped them, the floride in the water was irritating them.  Well, it took some searching, but I found Zero water and have been using it since.  I hardly ever suffer break outs anymore and my stomach does not hurt hardly ever. I can tell when I need to change the filter, ther water starts to taste bad. I am visually impaired and can not read the little thing that lets you see the numbers for the water.  I love you company and am so grateful~~