I have the water quality parameters from my municipal supply and due to chloramine in the water, I am running it through a Culligan EZ-4 filter system. After filtration, I do not know if the water quality parameters required in the brew water calculator (Ca, Mg, etc.) have changed in comparison to the inlet conditions from the municipality. I assume I'll have to get an independent lab to test it post-filtration. Is this correct or does someone have a better solution?