VIVOSUN Digital pH Meter, 0.01pH High Accuracy Pen Type pH Tester for Hydroponics, Household Drinking, Pool and Aquarium, Black, UL Certified

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 as advertised. Comes with buffer packs to calibrate. Would 100 percent buy another when this ones life is up. Thanks yall! Vivosun is my go to grow store online. Always what i expect! Love yall!

Random Number Generator. Bought several of these and really wish I had just bought test strips. I need a ph check on my water/nutrients daily for my plants and these will not work after about 50 days and 50 reads. That is with me recalibrating them often as they instructed. some of them work for a bit but always drift and after a while the simply don't work. I calibrated a brand new one and after 2 reads of other solutions it read the 6.86 calibration solution as 7.04 and keep in mind this was a brand new one I had never used. with ph strips i can buy hundreds for the same price as one of these.

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.

This is the second of these PH meters I've purchased. There are a number of negative reviews, so I was a little concerned but went ahead and order one. The first meter calibrated easily and (apparently) accurately. I used the three point calibration, then tested my fish tanks and compared the reading to the drop type ph test kit I had been using. It was spot on as close as I could tell with the test kit. I used the meter for a week, every day on several tanks as I changed the ph. It tracked these changes as I would have expected it to. It worked very well for me so I ordered a second PH meter. (I have fish tanks in two locations.) I then used these two meters side by side. They vary from each other by 0.10 points. The second meter did not calibrate as easily as the first, and the calibration was off slightly. I will try recalibrating, but it's as accurate as I need now. I'm very satisficed with them and would recommend.

Thanks for your fast shipping. The product was very useful for my application.

Best pH pen I have ever used. I’ve had the cheap ones before but they never calibrated properly. This one was perfect on the first shot. Vivosun may be my new favorite brand for growing supplies!

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

Works great

Funktioniert gut sogar mit Leitungswasser

Works well

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).