What I did was get a Culligan drinking water system. This
generates around 30 gallons/day of RO water. Makes great
coffee, too. If I'm not mistaken, it cost about $300.

Mike wrote:

I am evaluating RO units and would like some help in choosing between Kent
Marine's Bare Bones Unit and their 3 stage Hi S units. My tap water is high
pH (8) and high GH (12). My objective is to lower the hardness and pH so
that I can raise and breed apistogrammas and blue rams. Thanks in advance
for any help.