Water Quality

[MadReefer]

Moving into the new house it has both city and well water. I tested the water from my kitchen faucet when we first moved in and was about 140ppm.
Since the sprinkler system is activated and runs off the well water I tested that. Well water is 23ppm and now city water is 98ppm.
I assume its better to use the well water until the TDS changes as my RODI filters would last longer.
Just looking for input if my assumptions is correct.

 

[radiata]

DI filtration has a problem with high CO2- https://reefs.com/forum/general-discussion/310126-interesting-rodi-finding-1.html
So, which is the better input water might depend on which has the lowest dissolved CO2.