[jk999]

Just 1000 a,week and you get charged £77 a month glad I'm not on a water meter

[combat1]

£77 per month is for total water use. Home and business.
I fitted a sub meter before the pure water system and looking at the records, use anywhere between 5 and 8 000 litres per month to make 4000 plus litres of pure.
Probably varies according to the state of the resin and quantities produced.