John, you should see my system. I have a Cirqua RO that I got used from a friend. He got it from a coffee house that was going out of business, a steal of a deal. It has 2 RO membranes that are each 2' long (in the stainless steel sleeves in the middle of the unit) along with pre and post filters. It has a huge pump that makes 120psi and it makes about 30gph. I added a 'normal' DI canister and have to refill it every 4 to 6 months. I use about 100 to 150 gallons per month (mostly freshwater for evaporation from 4 tanks). I have a 45g RO/DI storage tank and a 120g reject water storage tank (an old cistern) and we use the reject water to do laundry.
