YINMIK pH EC Meter for Water Hydroponics, PPM Meter for Nutrients, Measure pH PPM Conductivity Temperature of Hydroponic Garden Water and Nutrient Solution, EC pH TDS Meter for Water, Aquarium, PoolClimatePartner certified

So far it works fine. My last meter (different brand) only lasted about one year so I'm hoping this will outlast that one. A word of advice. Calibrate about every 4-6 weeks.

Great product! Easy to set up and very useful, especially considering the price point. No more trying to interpret shades of color on a paper strip to guess the PH.

Manufacture replied and sent a replacement meter that is working fine. My mistake was not purchasing two meters so when one failed I had a second to continue measuring nutrients for my hydroponics. Meters sometimes will fail and I should have had a replacement handy since I needed it everyday. I may have gotten a marginal meter the first time. The manufacture did stand by their product and sent a replacement quickly. The original meter worked fine for 2 months, but then stopped calibrating Was told by Amazon no replacement after 30 days how nice! I give the meter 4 stars since they sent a replacement, but should have worked longer the first time. For the price you can't really expect a high quality instrument.

Easy to calibrate and accuracy is very good.

I have seen it so many times with new people in plant hobbies that just have to spend a fortune to try and buy a good grow. I understand that high quality equipment is very important with horticulture but you can accomplish the same goal without spending a fortune on the best name brands. I've had two of these in the past 3 years and that has been twice as long as my Blue Lab and Apera meters have lasted and they were over 6 times the price of this cheap chinese meter so take that as you will

This works well. You need to make sure it's kept clean and keep up with the calibration. For the price, this is good & accurate. It gets the job done.

The temperature reading is off by 5 deg F when compared to 3 other thermometers that agree on the temperature. I don't need to use the temp. function but if it is off then I have low confidence in the other readings. Yinmik tech support, which appears to be AI, told me that the other three thermometer reading could be wrong. Update: I can insert the meter into the same aquarium three times in a row and get 3 significantly different readings and that is after doing a calibration. Without calibration the initial reading of an aquarium of pH 7 will read down in the pH 5 range.

This is a good accurate pen. Just recalibrate it occasionally and it will serve you well. This one was actually calibrated to 7.00 right out of the box, unlike several other brands that have promised that before. I check this one with other pens to verify accuracy and it's right on usually all the time.