Review on 🧪 Apera Instruments AI311 Premium pH Pocket Tester Kit: Waterproof, with Replaceable Probe for ±0.01 pH Accuracy by Dustin Miller

I have tested 4 different meters and I explains the reasons for my rating. My colleagues highly recommended this gauge to me and after countless calibrations on my other gauges I gave up and bought it thinking it would solve my constant calibration problems. Unfortunately it isn't. I ordered one and it immediately showed my tap water at 8 ph so I wouldn't start using the device with calibration on first use. I replaced it. This meter is better than the two flatter pH meters but the other waterproof meter I got from Revain is just as good. Water resistance is a nice bonus, but the main downside I wanted to address is the frequency of calibration. Even though I've cleaned it with tap water AND bottled distilled water, I still find that it needs to be recalibrated after every 3 or 4 uses. I always try to keep it a little wet. If you look closely, you'll see that the sensor here is the same as the fake one, but better protected. That's why I have to calibrate it just as often. I've also found that it takes a lot longer to register the pH and I often have to turn it aggressively in the water because the protective blue plastic around the sensor blocks the water and also traps air, leaving you with a bubble or two see when turning vigorously. . If you're not in the high fives to low sevens range, it literally takes about 2 minutes for the reading to stabilize. I find others do it in about 30 seconds. The only advantage I think this has over another fake block (I think) is that it comes pre-mixed with pH solutions and a KCL solution. For the difference in price you could easily buy 3 plastic containers and a bottle of distilled water. The case is good but absolutely not essential and I just think there is a better price.