Wed Mar 17, 2010 9:29 pm
I really don't think softened water will "reduce the life" of your RO; the issue I 'know of' is this: the rejection ratio of sodium ion is lower than that of Ca and Mg. This means the following...you are taking high Ca and Mg water for example, replacing it with high amounts of Na. Now you take an RO membrane and reject a lower proportion of the sodium...what are you doing? Instead of leaving some calcium and mag, you are leaving more salt which is really not a good thing for beer, more so with high SO4.
I would personally stay away from cheap units. The way RO works is by passing water over a membrane, good clean water goes through and the crap is rinsed by waste water...read: WASTE. A cheap RO may take 15 gallons of water to make 1 gallon of relatively clean water. A high end unit may be more like 5:1 waste to final. If you spend a bit more in advance (like with a watts unit for closer to $400) you will make better water and likely make up the costs in the lifetime of the unit. But the important part to me is better water, not so much the cost overall. Now, if you like crappier water with high Na then go for it.
Another concern, paper vs. thin film membrane. Paper membranes (from my limited knowledge) require chlorinated input water to keep the cellulose based membrane sanitary. TFC should have a carbon filter before the membrane since chlorine will break down the membrane. I would talk to a water professional (Kinetico or Culligan) and get a water analysis before you buy anything. Worst case, you can DIY and buy either a high end unit (Watts) or a shitty unit (eBay/Home Depot). Excuse my water arrogance but, honestly, beer is largely water and I don't like to lose control of the majority of my beer to a cop out of a unit.
Where is AJ to put me in my place and set things straight?
Now if anyone is feeding well water to an RO you really need to have a handle on your iron and crap like that before you throw it at any membrane. Crap in crap out.
On Tap: Dark Mild (x2), Honey Hefe
Fermenting: A.Bastard Clone, Wee Heavy, S/70, Eng. Barleywine
On Deck: ?