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 Sam Lund

Well I've been using it for several months and so far there are no problems. Calibration was a little tricky, I just had to keep trying until I got it calibrated the way I was supposed to. I use it about every other day and check the calibration about every few weeks and so far I haven't had to recalibrate. It is very important to rinse the probe with some distilled water after use, then I shake off the water and inflate to dry before putting the cap back on. It seems accurate enough for my needs, when I test it to see if it's calibrated it's within a few tenths and stays that way. Very easy to use, I would like the display backlight to stay on longer, but turning it off and then back on fixes this problem. The TDS meter also seems to work very well. I have tested it with reverse osmosis water from a 6 stage filter system and so far it is working as it should. 5 stars recommend to anyone who needs a ph/tds meter.