I living inL.A I am freshmen whenI asked store about RO and drinking water has any differen there say salt water need purewater to made .but bouth water gothrough filter. even my house use 5 stage filter to made drinking still not pure enough I confuse , Please give me a hand . Thank you so mouch . also I looking for someone living in IRVINE we can share imfortion my phone 949-6359988 cell 949-2446498 Thank you again.