My Hanna soil pH tester dried out and quit working (my fault) and they replaced it with no problem on warranty, but the rubber tip they provide to keep it wet isn't very good and it dried out again and got screwy. Probably off warranty now.
I'm using a Milwaukee pH meter now that only reads 1/10's, but it holds its calibration for a long time and still works after it dried out when I let it sit out all night without putting the cap on. I think
@DCLXVI recommended it (thank you very much).
The Milwaukee Instruments compact pH pen tester is often used to help maintain pools and aquariums as well as improve results for growers and quality in a range of food and beverage uses.
milwaukeeinstruments.com
Be sure and buy the storage and calibration liquid, they're not included:
Milwaukee is your best source for pH, TDS, ORP testers, meters, monitors and controllers. Upgrade to Milwaukee for affordable, high performance digital measurement.
milwaukeeinstruments.com
Probe calibration is a simple procedure for optimal performance and should be done any time your readings become suspect. Calibration should be performed at least once a month.
milwaukeeinstruments.com