VIVOSUN Digital pH Meter TDS EC Meter for Water 0.01 Accuracy Hydroponics

After reading several reviews on this and other similar models I decided on this two pack PH and TDS. I recently installed a reverse osmosis under kitchen sink with a tds digital display and wanted another way to check its accuracy along with what ph the RO water was putting out. Item arrived quickly and after reading instructions I decided to give it a test. Batteries were already installed and additional batteries were included so that and they both were already calibrated so two pluses from the start. I filled a glass with reverse osmosis water and another from bathroom sink. Tds for bathroom were 107 compared to RO water of 9. This is the same reading my RO system shows so I assume its pretty accurate. Next I tested the PH. Ro water was higher than bath sink water but this units numbers jumped around a bit. Although the numbers did not display steadily i was able to get a good reading and am pleased with the results. For the price I find the two units a great bargain and much better than the water test strips I was using. After my initial tests I highly recommend these products as they appear to be accurate and easy to read.

If you’re looking for an affordable way to check pH, TDS, and EC without spending a lot of money, this is a great option. It gives you several useful readings in one device and is much more convenient than buying separate meters. The readings have been consistent for what I need, and the auto-calibration and temperature compensation make it easy to get started without a lot of messing around. The display is easy to read, and having the hold function is a nice bonus. For the price, I really don’t think you need to spend more unless you have a specific reason to buy a higher-end professional meter. This one gives you the important functions at a fraction of the cost. Definitely one of those purchases where you get a lot for your money.

notice a white fungus on that back of the yellow ph tester weird and disgusting

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.

I have a scientific grade PH probe that has been in continual use on a 65 gallon discus tank for 6 months and it was time to recalibrate as part of routine maintenance. After 6 months of use, probe had barely drifted. I used PH 4.0 and PH 7.0 calibration fluids. Probe was spot on with the 4.0 and read 7.1 with the 7.0 so it only needed a very minor adjustment to bring it back into perfect calibration. I used this probe as a comparison with the VIVOSUN. The VIVOSUN readings straight out of the box were pretty far off. Measuring the PH 7.0 solution, the VIVOSUN reported 7.6. Measuring the PH 4.0 solution, VIVOSUN reported 3.65. I calibrated the VIVOSUN using the provided powder for all 3 PH solutions provided as this should provide the most accurate readings per the instructions. Immediately after calibration, I poured fresh 4.0 and 7.0 solutions and the VIVOSUN results were at least .5 off in both directions. Poured fresh solution AGAIN (after rinsing probe in RO water) and once again results were way off (but different from the results it just reported from the first fresh solution pour. I then compared with test strips and the test strips matched the results from my scientific probe. In short, do not rely on the pH meter and I would go so far as to say you need to throw it in the trash ASAP. The TDS meter is also flawed. There are 4 modes of display, according to the instructions whichever mode you choose will remain the default until you change it.. (e.g. Power it off today and tomorrow when you power it on, it should default to the mode it was in when it was powered off.). It does not do this. Not only that but in the middle of taking a reading, it will just randomly switch from measuring PPM to EC or from Celsius to Fahrenheit. I don't have anyway to validate the EC or PPM readings but judging by what I can validate, I would not trust it in any way, shape or form.

I purchased this set to monitor my hydroponic solution strength and pH. The EC meter just stopped working after moderate use after one year. I also didn't like having to switch from PPM to EC every time I turned it on. I also noticed the readings were different when I switched from C to F. I think the pH meter is accurate enough for my needs. I calibrated it once a year and it didn't veer to far off. I mean the price is reasonable enough that I can buy a new set, but I shouldn't have to.

This product works as advertised. You have to calibrate it first using the provided ph packets but once you do that it is good to go and offers accurate reading. This product assembly and price range makes for a nice introductory ph meter as opposed to a more premium, and also costly, assembly, yet it is still so much better than a manual ph test strip. I would recommend this product to anyone looking for an affordable digital oh tester. I like the vivosun brand and the products they have offered so far.

Wanted to check the pH level of several home wells water for home brewing, economical way to do it, more of a toy than anything so i cannot attest to the accuracy but i assume it's accurate enough, especially for my purpose.

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

Macht seine Aufgabe gut.

Arrived not working, tried replacing the battery but no joy so sourced an alternative

Great product

TDS meter are working fine but for the PH meter I personally don’t arrive to fully calibrate it as all the time I do the PH 7 then PH 4 and when it’s arrive to do PH 9 it’s return to PH 7 so impossible to complete the calibration.