VIVOSUN Digital pH Meter 0.01 Accuracy Pen Tester for Water Hydroponics | ±0.01 pH Accuracy, ATC, Auto Calibration, Backlit LCD, Memory, Compact, UL Certified, for Hydroponics Aquarium Pool Drinking

Although it may be a little delicate to calibrate upon first time using. Insure solution temperature is ~75 degrees F. Measure out 250 ml distilled water. Insert the meter into a cup pour into another cup until you reach the line on the meter. Turn meter on holding down the calibrate button for 5 seconds then release. Press Cal button one more time. I did not get a display showing "cal" like some of the YT videos. This generates confidence in the meter concerns. However, I had a lab tech at the university check the calibration in a buffer solution of 7.0 and the meter showed 6.97. First pH meter that works and provides accurate results.

Works perfectly

Did not work. Was sent a meter that had dried salt crystals all over it and water droplets in the LED area (under the clear plastic layer). The meter will not calibrate and is non-functional.

Item Reviewed: VIVOSUN Digital pH Meter, 0.01pH High Accuracy Pen Type pH Tester for Hydroponics, Household Drinking, Pool and Aquarium, Yellow, UL Certified ℹ️ Summary I picked this up for pH balancing water that I use for my indoor grow tent and it has worked great for that purpose. For $10 at time of order, you’re getting a meter from a reputable brand that won’t break the bank and does exactly what it’s supposed to do. Included in the package are a nice plastic storage case, extra batteries, and a set of pH calibration buffer powders (6.86, 4.00, and 9.18), which was a nice touch. Calibration was quick and easy and I’ve only needed to recalibrate about once every 3-4 weeks. Readings also seem accurate and consistent. My only real complaint is the build quality. It definitely feels made from cheap plastic and while the buttons are clicky, they still feel a little flimsy. Overall though, I’m happy with this purchase and can comfortably recommend it as long as your expectations match the price point. ✅ What I Like - Low-priced. - Gets the job done. - Comes with a decent plastic storage case. - Includes pH calibration buffers (6.86, 4.00, and 9.18). - Comes with an extra set of batteries. - Readings seem accurate and consistent. - Calibration process is simple. ❌ What Could be Better - Build quality could be better. - Feels made from cheap plastic. - Buttons feel a little flimsy despite being clicky. Final Verdict | ⭐️⭐️⭐️⭐️☆ Here is how I rate items: 5 ⭐️ = Completely exceeds expectations. 4 ⭐️ = Works well with minor concerns. 3 ⭐️ = Does the job, nothing special. 2 ⭐️ = Some things work, but lots of issues. 1 ⭐️ = Didn’t work well, not worth it.

The VIVOSUN digital pH meter is easy to use and gives quick readings, which is convenient for basic testing in hydroponics, drinking water, or pools. The pen-style design is compact and portable, and the display is clear and easy to read. However, the accuracy can be inconsistent unless the meter is calibrated frequently, and the readings may drift over time. Build quality feels somewhat lightweight, and for more precise or professional use, it may not be fully reliable. Overall, it’s an acceptable 3-star product for casual or occasional pH testing, but it may not meet expectations if you need high accuracy or long-term stability.

Great for the price

I never thought I'd become an amateur chemist in my own kitchen, but here I am, wielding the VIVOSUN Digital pH Meter like a modern-day Merlin. This little gadget has been a revelation! It's so easy to use and calibrate, even a goldfish could probably do it (though I wouldn’t recommend letting them; they’re notoriously bad at following instructions).Now, I must confess, this is my second round with this magical device. Not because the first one failed me—no, quite the contrary. It's just that I found changing the batteries to be akin to defusing a bomb with tweezers and a blindfold. So, in the spirit of "treat yo' self," I decided to just buy a new one instead. And let me tell you, it was worth every penny.Why do I love it, you ask? Well, it’s as easy to use as pushing a button, and calibrating it is a breeze—just make sure you follow the instructions. I learned that the hard way when I skipped a step and momentarily believed my tap water could be a secret chemical weapon, reading off the charts like hydrochloric acid. After a brief moment of existential dread and contemplating a call to the authorities, I realized my folly and recalibrated. Crisis averted. P.S. Don’t forget to get some PH down… you’re gonna need it if you’re reading this!

I can honestly say this little pH meter (black Vivosun) has exceeded my expectations. For such a low price point, I figured there would be considerable issues with sensor drift requiring constant calibrations however this little guy has always been within .1 pH when checking prior to the calibrations I have periodically performed over the last few months. Proper rinsing and storage as well as frequency of use are also important factors when maintaining accuracy with a pH meter however the quality of the sensor is also part of the equation. With that being said, this Vivosun pH meter appears to be well made. I would always recommend periodic calibration of a pH meter if you are relying on its accuracy regardless of the manufacturer. The probe is easy to use and easy to rinse after use eliminating any hassles and the removable probe cover provides protection during storage. The readings quickly stabilize which has also streamlined my testing process. Overall, this has been a great value and I would recommend especially if on a budget.

La calibration est simple. Par contre, par rapport à une sonde témoin, il est extrêmement lent. Il faut compter presque 10 minutes pour que le pH final soit affiché. Il faut donc le mettre longtemps pour à avoir le bon pH. Après 6 mois et une utilisation par mois, il deconne complètement. Mauvaise qualité

Firstly it's not expensive, it didn't come with buffer solutions and only three of the batteries were functional and loose in the package. Other than those concerns it performs well and is easy to calibrate..... I had ordered extra buffer packs!

Funktioniert gut sogar mit Leitungswasser

Buscaba un medidor de ph con poco tiempo para comparar precios, y sin aparatos de medida para comparar su exactitud. De los 3 sobres de calibración sólo usé 1 (el de 6.68, que es lo más cercano a lo que quiero medir) Curiosamente, cada vez que lo enciendo empieza en 14...y tarda unos 2 minutos en llegar a la medida. Las instrucciones "regulinchi", pero en Youtube hay tutoriales magníficos. Creo que he pagado 3 euros más por la marca (por eso no le doy 5 estrellas).

Esperaba fuera algo sumamente sencillo de usar, y necesita ciertos insumos que los trae incluidos pero al terminarse no se donde los podré conseguir. No supe como usarlo.