Hi I live in a hard water area also at my house I live on a new build so I'm on the meter and fill up still round my mums who is off the meter - I run it through RO then have one vessel with di to polish off to 0.0ppm - my ? Is how quick would I go through resin using duel vessel in van running straight tap water in tank as takes up to 4 hours for 200 litres atm - Tap water would go in around 250ppm. Thanks