Zacro Digital pH Meter with Pack of 6 Extra Buffer Powder, pH Pen Tests Water, Aquarium, Pool, Hydroponics, Auto Calibration Button, with ATC, 0.00-14.00 pH Measurement Range

Terrible product. I bought three and needed them for a college chemistry experiment. I didn't need them to perfectly accurate, but they weren't even close. They read between 4.00 and 9.00 in distilled water out of the box, so I calibrated them and they still were way off and continuously fluctuating. I thought it might be the distilled water, so I bought three different kinds of distilled water and tried to calibrate again. They were still wildly fluctuating. Somewhere in this process, the digital readouts on two of them stopped being legible. This product is a huge waste of time and money and now I don't have the tools I need to complete my experiment. I would guess that higher reviews on here are planted.

Good product, I'm sure, but characterizing ionic properties of liquids is much more complex that simply measuring pH. I was goint to use it in coffee, but I think pH is only a small part of what controls coffee quality.

Great pH pen, just calibrate it and it's good to go. I've had it a few weeks and it stays calibrated. The back light goes off pretty fast but you can hit the calc button really fast to make it re-light.

Seems to work well, and arrived in the expected timeframe. My only gripe is the time it takes to get a stable reading, I've had to hold it in the water as long as 45 seconds or so until the reading quits fluctuating and settles on a value.

I am new to hydroponic and have discovered that having the correct PH is extremely important in helping my tomatoes uptake nutrients. I started with the eydropper and ph test solution. This works fine but if you have to correct the PH it takes a little more time and depending on the number of plants you have you can go through a lot of solution. This PH meter is very easy to use. Just turn it on by pressing a button and imerese into the water just enough to cover the test port. I get an accurate reading each time. Of course you might need to calibrate on ocassion. This is also quite simple as the meter comes with calibration solutions. I have had mine for a few months now and have not had to calibrate at all yet.

This thing will not hold a calibration. It was way off just a couple hours after calibrating it. :( I guess you get what you pay for.

Works as described and is in my favorite color, lol. I purchased this ph meter as a backup, but i like the calibration method that is easy to use.

It's been reading good so far. We'll see how long it'll hold