Hi guys I have been cleaning traditionally for 20 years now I have to get the WFP system as I do very posh school in Surrey . Due to health and safety issues I need to poll system and I haven't got a clue about it as anybody got any ideas what sort of system I need hard water area et cetera The more I read up about WFP system the more confused I get ie ro or di ? What is the best system to use moneywise as it is a lot of money to fork out I hope you understand what I mean any information would be very much appreciated !!!!