Going into the DI stages, I read 3 tds. About 130 out of the tap. After first DI stage it reads zero and I have a second DI to make sure I fully exhaust the first one as it does “something” past the color change indication.
TY all. I just set up a used RO/DI and have dual RO membranes and was getting 12 tds but after running for an hour the TDS dropped to 4/5 which is prolly more in line with what I should expect.