[christopher b]

Ok I said get away with 2, that by no means says I use 2. if the TDS moves of 0 the resin is done with.
I will be honest I have used at 3 but this was on a first clean that looked as if had been in a mud fight! once all the heavy muck was off we was back next day armed with a reading of 0 in the tanks.

[Ian Rochester]

000 all the time, every time. 

We have a static RO (HF5) producing 2000ltr/day at 002

Three vans that are tested daily, if it reads above 000 the resin is changed.