YINMIK PH Meter, Digital 4 in 1 PH EC TDS Temp Meter for Water Hydroponics, Waterproof DWC PH and EC PPM Water Tester with Backlit for Nutrients Growing, Indoor Garden, Home Brewing, Pool, Aquarium

Works great

Item was delivered on time. One of the nicest meters I have ever bought. The display screen is very easy to read and very bright. Simple instructions. It even came with extra ph solutions. It seems to be built very solid and the size is perfect. I didn't even calibrate it before first use. I am going to say that it is a quality meter with a low price. Will buy again.

I have had to replace it already it went out of calibration & won't recalibrate again. I tried the recalibrate powder but it wouldn't do the 4.o cal. Did 7,&10.so i looked for a replacement prob tip but what I found was only $5.00 cheaper than a new meter so I purchased a new meter! Meter is fine when it's working right.

I’m actually surprised at how well this ph meter works. I owned for 6 months now and started to have doubts about its accuracy. I purchased a more expensive $85 meter and after calibrating it I tested both meters in water.To my surprise Both came out with the same reading. I have only calibrated this meter once when I first got it. Very nice to see a $20 meter holds up to a much more expensive one. This only complaint I have about this meter is lack of the backlight staying on while I measure the water. For the price this is an extremely well made meter that holds calibration well over time. I would definitely recommend this meter

When I first used this meter I of course calibrated it. It held the calibration for about a week then the readings went wild...oh no. So, I calibrated it again and it has been consistent ever since. I routinely verify its reading with another (way more expensive) meter and some paper pH test strips and this YINMIK is spot on. I like it especially for the price. It is my 'daily driver'.

This pen is very easy to setup. Comes with batteries ready to go. Comes with packets to balance the pen. You will need some distilled water to help calibrate. I recommend it. So far so good few years in.

Probe is reading pH's of buffer solutions almost 1.01 whole point lower than each pH packaging implies should be (4.00 solution offers 3.01 reading, 7.00 solution offers 6.01 reading, and the 10.10 offers 9.11 reading). pH of buffer solution was tested w/ pH strips to ensure the solution values were accurate prior to attempting calibration, and of course mixed the powders with 250ml of distilled water as directed. The whole point of calibration is being able to adjust output readings based on input values so that output is setting out the correct measurements. This pH probe is useless as is unless I want to add .99 to each and every measurement I take, though I have no confidence in the product anymore anyway. Also, the cap contained a sponge that instructions indicated was supposed to be moist. It wasn't, and there was some kind of unknown clear slime on the inside of the cap that I'm sure the probe had contact with or that somehow leaked from the probe. Either way, I'm not happy. Product packaging instructions indicated it could be returned or replaced within 12 months, but Amazon's stated option is only 30 days. We're about 15 days past that, so I guess I'm just ripped off. Sometimes it reads straight 0000 across unless you kind of knock it against the glass, insinuating that there is a faulty connection or chip in there somewhere (despite unscrewing and ensuring everything is connected properly). *Editing to add* This product did not come with the calibration solution for EC/TDS settings either, nor the storage solution (I read in a review that product finally calibrated correctly after being submerged in SSolution for 24 hours, and given the cap sponge was so dry, thought I would try BUT I don't even have that option here. Did add a couple of drops of distilled water to cap sponge as per instructions, but it does not seem to matter much) And, only 2 packets each of 4-7-10.01 pH buffer solutions, which is also unhelpful beyond 2 calibrations, IF they had worked in the first place.

I was in the market for a decent pH/PPM Meter that wouldn't break the bank. A few people recommended this one, and most the reviews I read here were good so I went for it. Shipping was quick and the meter came with good instructions and buffer solution. I was able to calibrate with no issues. The protective cap has a protective sponge that is to be kept moist per the instructions, and you're instructed to add a little pure water to the sponge if it dries. The manual also states water droplets are added during production to maintain moisture of the probe. Since receiving and using the meter, I had no issues with the sponge drying out. I followed all instructions that were provided to, and since I've used a similar meter in the past I was comfortable when using. About 2 weeks after using the meter, I removed the protective cap, only to see the sponge was covered in what looked like white mold. The probe itself was also moldy. I carefully cleaned the probe and cap, but with each use, the problem continued getting worse. I reached out to the email provided in the manual as I was unable to reach out via Amazon. Response was quick, as follows : "We are sorry to hear that the sponge is moldy. As the weather temperature rises, no preservatives are added to the sponges, causing the sponges to become moldy. Please clean the electrode tip with a cotton swab or brush, and use tweezers to pull out the sponge. This is a newly upgraded electrode, even without a sponge, it will not affect the pH reading". I did question removing the sponge, but I was assured it would be OK. I very carefully cleaned the electrode like Lucia told me to. For the time being, it seems to be working just fine, but I'm nervous that it will malfunction. I'll update my review if anything changes.

Followed instructions exactly. Tried 20 times. You’re supposed to turn on unit, place it in 7 ph calibration solution, let it settle and then hold cal button for 5 seconds. That’s supposed to enter calibration mode. Tried holding everywhere from 2 seconds to 30 seconds. No matter what it won’t calibrate making it useless. Unless the seller can fix this I’ll be sending it back. Waste of money and most importantly time.