I currently have an HM Digital TDS-3 meter and I despise it. It is horrible to try to calibrate with the screwdriver that you move a billionth of a mm and the meter goes up by 50 ppm. The Hanna TDS-1 uses the same type of screwdriver calibration. I'm looking for something easier to calibrate.
The only hand held TDS meter that I know of that doesn't use a screwdriver for calibration is the HM Digital COM-100 meter. It is also top of the line, and rather pricey.
Anyone know of any other TDS meter that doesn't use that stupid screwdriver calibration?
EDIT: Just found the Hanna HI 98311 Waterproof Low Range meter self calibrates like their pH meters. Excellent! However, just as pricey as the HM Digital COM-100 meter!
EDIT 2: The Hanna Primo has automatic calibration with 1382 ppm fluid. It suggests 2% +/- accuracy, but I wonder how accurate it is when it is very close to 0? I will send email. This meter is only $20.