Find out ur tap tds.buy a tds meter!
Buy a 25l vessel and a bag of tulsion mb115 from pure freedom.
Connect up with some hose and fill up barrels or tank.
Also I would buy a small vessel for fillin up on the job.say a 2.7 l.you can also use this is tandem with the bigger vessel when the tds rises in the big one.its a very simple process.
Off to work now.ill post more later.

Regards
Dazmond