I understand that approach, and while its not one im taking at the moment I see the value in having complete control over your water. There are some environmental concerns in doing RO though in my opinion. In my country tap water is generally very soft, mine comes out with 60 TDS and is very lightly chlorinated, and I think fairly stable throughout the year. Ive heard of lots of disasters in other countries though, especially from the US of the so called super chlorinator events that have wiped out whole fish rooms, really sad.