Type TDS Meter on a search on ebay they will bring up the ones for window cleaning and at a very good price as well.Roy
ok keep ya knickers on you dont need a tds 4 unless your using hot water what you need is a tds 3 that gives you a tds reading and also enables you to hold the reading ..............tds1 just gives you a reading without it holding does that help
what you need is a tds 3 that gives you a tds reading and also enables you to hold the reading ..............tds1 just gives you a reading without it holding does that help