Varied TDS Readings

[mark]

RO on it's own won't bring to zeo, that's why the di follows.

I just checked my water, 5 after the ro, then 1-2 after the di but then di last changed in July and haven't cal'd my meter so not getting worked up.

Have also noticed a rise in TDS after sitting and seen few other post the same.

[Jaws]

So would you say that's normal or harmful?

[mark]

not ideal since the idea of ro/di is to bring TDS to zero, not the end of the world as there's tanks out there using tap water.

[Canadian]

I know I wouldn't be satisfied knowing I paid a couple hundred bucks for an RO/DI unit and I was still getting TDS.