> That sounds quite right.
> 25 years ago I was in a laboratory that used stuff like that.
> One cylinder H+ swappers and the other one OH- swappers. Was regenerated by
> rinsing with HCl and NaOH. Colours dark brown and light brown.
> I still have one litre of both types, but I've never tried to use it because
> it looked so difficult to balance the system to get neutral water out of it.
> They also had an electronic measurement equipment to gard the output
> quality, which of coarse I couldn't do that easily at home.
>
I could probably rig something like this up. The problem with electronic
pH meters, is the cost of the probes (which I think are also quite
delicate). By the time we did this, and managed to source the resins &
HCl + NaOH, I think we'll find that Reverse Osmosis units weren't much
different in price!
Richard