Sending additives down the fresh water AWC line, OK?

[SteveWin1]

So, I have 3 RO lines going from my tank, up to the attic and over/down to my garage, where I mix salt water and make RO/DI. 2 lines are used for AWC and one sends RODI to my kalk stirrer. I've got one DOS in the garage swapping dirty water for new saltwater. That works great -- I don't hear it at all. Then I got a second DOS for the kalk stirrer. I had originally planned to put it in the garage with the other one, but realized I would have a fourth head that I couldn't use without running a fourth line, so I put that one under my tank. Unfortunately I have to max out my kalk addition to match evaporation and still very slowly lose alkalinity, which means the DOS runs fast enough (25mL/min) to make a significant amount of noise. I've semi-solved this by dropping the kalk addition to 7mL/min during the day, to cut down on noise (still audible, but better), and then blasting the difference into the tank when we're asleep (wife has a white noise machine so we can't hear it at this time). This causes slight water level fluctuations since I can't add enough to match evaporation during the day, but does help level out the nightly pH drop. I'd like to just move the second DOS to the garage, but I don't have a fourth line going through the attic to be able to use the extra head on the DOS. Do you all think it's ok to add a 3 way "T" connection to my fresh saltwater line and just dose directly into that, downstream from the DOS that pushes new water to the tank? Is stuff going to precipitate in the lines and clog everything or will it work ok?

 

[PeterC99]

I’d be careful with the saltwater T solution. I have Kalk pumped into my sump via the DOS as well but from a reservoir of Kalk and RODI water. I’m constantly cleaning the end of my DOS line that dispenses the Kalk RODI. It’s constantly crusting up.