since you re heading off to dad. i just got a zerowater. but we ve always used brita. it s two stage-filter. doesn t compare to zerowater s 5-stage. this meter shows how much stuff, or dissolved solids, gets left behind. our tap water is 220. brita? 110. seriously? but zerowater- let me guess. zero? yup, that s how i know it is the purest-tasting water. i need to find the receipt for that. oh yeah, you do.