Help!I have new ro-man 4 satge ro unit(came highly recommended)
After getting 000 readings for first batches of 200ltres produced

I left it for a week before needing to produce more water.I flushed system for 15 mins and discarded first 10 litres to be safe.BUT water is now 004
Tap 380 -before di -18 after di004
Does anyone have any ideas about what has happened?Or more specifically has anyone with a r0-man system experienced any such probs?
I have noted people say you can use 004 -005 water,but as a new wfp,er for confidence sake I really would feel happier using 000, so that poor results are definitely not down to water.