Happy Thanksgiving,Need help. Major TDS issues.

[cane]

Setting up my new 340 gallon system. Over the last week I’ve been making RO/DI water and it’s been coming out at zero. Once it hits one I change out the DI resin and it goes right back to zero. But for some reason I tested the water in the tank just for kicks (It’s 85% full now) and it’s reading 666. what the heck. The water coming out my home only reads 189. The water I’ve put in the sump so far from the RO holding tank that hasn’t gone up to the tank is reading 95. Last the water again is coming out the RO/DI at 0 and as of this morning the water in the Holding tank is at 1.

 

I have not mixed in the salt at of yet. I’ve just taken a few heaters and pumps out my salt mixing bin and put them into the tank.

 

Here is the sequence

 

House: 189 —> Coming out RO/DI: 0 —> Holding tank: 0/1 —> Sump: 95 —> —>Tank: 666

 

This is a brand new setup on the second floor of my home with a basement sump and about 40ft of PVC plumbing.

 

I do not understand how this has gone up so high.

 

Please help. I REALLY DO NOT WANT TO DRAIN THE TANK

[cane]

As I sit here and think I just realized I did put in about 40gal of saltwater that was left in the mixing bin when I started filling the system. Would this create that kind of reading. I’ve never tested the TDS of mixed water

Edited November 23, 2017 by cane

[Origami]

That 40 gallons of satlwater that you started with is doing it. By mass, saltwater is 35 ppt or 35,000 ppm. Even a 10% dilution would result in a 1750 reading on a TDS meter or possibly half that (875) if it assumed conductivity from 2+ ions like calcium). However, I'd guess that the TDS meter is probably not calibrated to read such high numbers accurately. But, short answer is yes, it's reasonable to have that 600+ reading in these circumstances.

[cane]

Thanks for the help Tom. I had no clue.