Could someone tell me in laymen terms what exactly a TDS meter is reading and what the acceptable reading should be? I know it is used to test RO water, what what exactly is it testing for? Is a reading of 0.06 good?
its reading the Total amount of dissolved solids per million parts of water. so if your tap water reads 200ppm tds thats for every 1,000,000 particles of water 200 of them are not water. on the output side of a RO/DI system you preferably want 0TDS but anything under 1 is generally accepted as OK
I think it is actually measuring conductivity and translating that into TDS based on conductivity for the typical sodium, calcium, mag values found in water. It is not reading things like silica or co2. I'd prefer if we had a direct readout of the conductivity rather than the tds translation which is not necessarily consistent from meter to meter.