Measuring TDS of RODI

trout · May 15, 2015

Hello,

I own a PINPOINT salinity monitor, which has a range between 00.0 and 200.0 mS. I use it to monitor the specific gravity/salinity of my tank water. Can I also use it to measure the TDS of my RODI water to monitor the performance of my RO unit's membrane? When I dip its probe to my RODI container, I read 00.0 mS, which is excellent.

American Marine Inc. has another product for the measurement of hardness of freshwater, but I wondered if I can use my existing salinity monitor instead, so that I can avoid unnecessary expense. I simply do not trust my handheld TDS meter.

Regards

Bulent

Randy Holmes-Farley · May 15, 2015

Theoretically you can, and I have a meter that can measure both, but no, the Pinpoint Salinity meter doesn't have adequate range/sensitivity to measure the needed low levels of conductivity to monitor an RO/DI.

They sell a different meter (Conductivity meter) for that purpose.

It is good for monitoring limewater (kalkwasser) potency, which is not easily don't otherwise by hobbyists.

trout · May 16, 2015

Randy Holmes-Farley said:
Theoretically you can, and I have a meter that can measure both, but no, the Pinpoint Salinity meter doesn't have adequate range/sensitivity to measure the needed low levels of conductivity to monitor an RO/DI.

They sell a different meter (Conductivity meter) for that purpose.

It is good for monitoring limewater (kalkwasser) potency, which is not easily don't otherwise by hobbyists.

Thanks Randy.

Would PINPOINT salinity monitor also be not adequate for checking the potency of limewater? When I dip my probe into newly prepared fully saturated limewater I get a reading of around 10.5 mS.