VIVOSUN Digital pH and TDS Meter Kits, 0.01pH High Accuracy Pen Type pH Meter ± 2% Readout Accuracy 3-in-1 TDS EC Temperature Meter for Hydroponics, Pool and Aquarium, Yellow Blue, UL Certified

5 Stars — Convenient and Accurate Water Testing Kit This VIVOSUN digital pH and TDS meter kit has been a very useful addition for checking water quality and monitoring pH levels. I’ve used it for pool maintenance and general water testing, and both meters have been simple to operate and easy to read thanks to the clear digital displays. The pH meter responded quickly and gave consistent readings after calibration. I also liked having the separate TDS/EC meter included, since it makes it convenient to monitor multiple water conditions without needing additional equipment. The compact pen-style design is lightweight, portable, and easy to store between uses. Another thing I appreciated was the straightforward calibration process and the included instructions. The readings stabilized fairly quickly, and the hold function on the TDS meter is a helpful feature when testing samples in smaller containers. Overall, this kit offers good value for the price and works well for anyone needing basic digital water testing tools for pools, hydroponics, aquariums, or household use. Accurate, convenient, and easy to use.

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.

Updated review: They work pretty well. You must calibrate them! The tds meter was way off and it doesn't come with calibration powder. The pH does. You can make 1 cup of each solution and store it for later use (I assume. I have saved it for later but only calibrated once so far) I bought this set as a backup. I dropped my main ph pen and broke the tip so I've been forced to lean on these. I calibrated the tds meter using my main tds meter and it's off by about .015 or so and that's good enough. The pH meter so far has been pulling it's weight.

As far as I can tell, it's correct. It takes a bit to go down to stop, but it gets there eventually.

So I bought this set wanting to try out actually tracking and adjusting my pH and EC of my nutrients for my little indoor hydro-farm. Like most people, I didn't want to spend a lot on my little hobby so I figured I would give this product a try as I actually enjoyed some other Vivosun products. I'll start with the TDS/EC Meter. It is actually decent and appears to be pretty accurate right out of the box. I've used it for a little while and it remains to be acceptably accurate so far without any issues. Good to go, this one I'm pretty happy with and will continue to use at least for now. Next I'm moving on to the problem child, the pH Meter. Wow. Where do I begin. I started off trying to figure out how to calibrate this little thing as the instructions drastically varied from all the calibration videos available online for it. Maybe they changed the method but once I figured out how it wanted to be calibrated I went through the steps and all was good. I tested it a number of times using various testing liquids and it was pretty spot on (at least within acceptable limits for my hobby, not anything that needs to be precise though). So I mixed up some of my nutrient solution, cleaned the pH and TDS meters as advised to in the manual and put them away safely. Fast forward 1 week, I pull out the pH meter and dip it into a cup of distilled water and it tells me that it has a pH of 10.3! Far from the value of 7 I was expecting to see. So I pulled out my other pH balanced liquids to test and every one of them was extremely off from what it should be. It completely lost ALL calibration after one use, and one week of storage. I'm sorry but that means I need to calibrate this thing every time I turn it on? And they only supply you with one set of calibration powder that isn't to be re-used? Absolute and complete garbage. The calibration costs for a year would be well into the hundreds a year for a $10 meter! Absurd. This is a product you should definitely skip buying. Buy yourself a 14-sided dice and give it a roll, it will give you a more accurate guess on your pH level than this thing every will. I would return it, but I was not thinking and threw away the packaging already.

I was told and did not listen to not buy a cheaper PH meter but I did it anyways. It is reasonably accurate at least so far, when it is brand new. However it takes a long time to settle, the calibration using lab grade buffer solution is... Not great. Basically I don't trust it and I bought an apera and compared the two. This one is probably fine if you don't you don't need perfect accuracy, but if you do, go ahead and get something a bit more premium. It is faster and more accurate than this one. This one also isn't really equipped to be useful in the long term. You need probe storage solution, which it doesn't come with. I also would not exactly trust the cap to keep it anyways.

I think it is the best product at this time with this price. Very professional and accurate. I have tried few others in the market and am satisfied with it. It comes with TDS and Ph meter, recalibration material that you may need after a long use or not-use being on the shelf. I was surprised to see additional batteries for both TDS and Ph device.

Very durable and versatile.Easy to use and no chemicals needed to mix everytime i use it

Really useful, I think the price is spot on and they have helped remove some of the guess work when it comes to pH and ppm

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.

Purchased to monitor the effectiveness of my Deionizing Water Filter that I'm using in a very high TDS location (Clearwater). Appears to work, though other that the spot free car wash, or high TDS without filter, very low with, there's no way to quantify the actual TDS numbers The instruments are splash proof at best, so don't submerge and not terribly sturdy, so don't abuse. But good value for electronic instruments you wouldn't expect to be able to own at a low price

its as expected