Hydroponics & Aquarium PPM and pH Meter Kit - Water Quality Tester for Pools Included Review

I have only used this product 3 times in the last 6 months to measure the pH of pool water. There was a serious problem today when the meter gave an incorrect reading of the buffer solution used to calibrate the meter. The gauge has drifted for the past week as a range of pH readings trended lower. I tested with standard buffer solution. The meter cannot display the pH value of the buffer. I bought this pH meter 8 months ago, can I return it?

The pH pen in this kit is not required. At first it got stuck reading all zeros. After playing around with it for a while it seems to be behaving normally, I did the calibration at 4.01 and 6.86. Then I tested some distilled water and the meter read 8.0 at first, after 1 minute it read 6.5 and after about 2 minutes it read 6. I bought another one of those yellow pH pens and after the same calibrations the reading it gave just cracked. Everywhere, everywhere, everywhere. The TDS test pen seems…

Both worked fine until I calibrated the pH meter a week or two - I used a solution I had on hand that was calibrated to 2 points, 7 and 4 - I had to use the bags they came with because the difference between the pH 7 solution I used and the pH 6.86 powder solution that came with it seems to be greater and an integer higher than just 0.14 - Human error? Probably maybe, but I also have, brand new from first use, 200+ ppm as my tank corona, a pH temp gauge for continuous monitoring, which is a…