7 in 1 PH Meter Gomass 0.01 High Accuracy ph Tester Digital for Water TDS/EC/Salinity/Temp/ORP/S. G/PH Pen Tester Drinking Water, Hydroponics, Plants, Aquarium and Pool

Great pen! Very easy to use great pen for the price , very durable, helps me to what needs to be done for my plants.

This thing has been a lifesaver and it functions as described and more. Do yourself a favor and get one of these

The first battery change and none of the buttons work now. Now it will only show ph. I can’t reset it or recalibrate it or anything. Useless after less than 6 months of use. Update: seller refunded most of cost of faulty meter and was very willing to replace. Thank you for your quick resolution!

I got this mainly to measure pH but the other functionality is nice. I am a big believer in calibration and I can calibrate pH and EC with standards so that's what I did. Calibration was easy and readings were stable after calibration so I assume it's fairly reliable. I'm not sure about the other readings because I did not have calibration standards, but I did have some test strips to compare with and this meter was reading similar values to the test strips. I wouldn't use this to gather data for a peer-reviewed journal article, but I think this is a great tool for routinely measuring your water quality especially if you are trying to preserve plumbing or testing a water filtration system.

Not calibrating is the normal for many auto-calbration meters. The old style meters that had a calibration screw allowing you to manually match the reading with the calibration solution the meter is sitting in. High tech auto calibration for low cost meters is problematic.

Not easy to calibrate

This pH meter is okay for basic use but not very reliable. The readings fluctuate a lot, even after calibration, making it hard to trust the accuracy. The build quality feels cheap, and the screen is difficult to read in certain lighting. It works, but only if you don’t need precise measurements. Spend a little more for something more dependable.