Tds changing?

[Notsolostfish]

I bought a hanna tds handheld meter. I calibrated using the solution. I noticed when i put it in my rodi brute container. Sometimes i get 1 and then when i move it in the water i get 0. I tested a cup of water from my rodi and i get 0. Is that dust interference on some spots of the water?

 

[KrisReef]

May be? The meter may detect almost zero when it detects ~0.5, so it rounds up or down around zero.

 

[Randy Holmes-Farley]

Carbon dioxide from the air can raise tds to 1 ppm, and bubbles can impact it ;lowering it).