Review on 🌊 Hofun 4-in-1 Water Quality Tester - Upgraded PH Meter, TDS Meter and Temperature Tester with Backlight, High Precision Digital Water Tester for Household Drinking, Pool, Aquarium and More by William Turner

I think if this kit was better it would come with a 250ml measuring cup to calibrate the ph tester and maybe a recalibration kit for more than one shot (e.g. link to ph packs or large vessel and measure at 250mL so you can easily recalibrate multiple times). Temperature and ppm tests were accurate and easy to use right out of the box. I think my unit looked pretty darn calibrated before calibrating, so even though it says it needs to be calibrated, you can test it in a few solutions that you know the pH of and find that it's already in the 0, 15 pH range of reality. Not bad. Again, I think they should make a calibration kit and add-on as an option to get more out of the pH tester, which was my main concern.