RO/DI Question

[hillegom]

The idea behind using a RO/DI filter is to rid the water of all TDS (total dissolved solids.)
This water is deionied and should have nothing in it.
So you need a TDS meter to see if the filter is working.
]The water comming out should be crystal clear and a TDS reading close to 0. Now that you have good water, you will have to add salt, then test this water, add calcium and/or carbonates, depending on what is lacking