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TDS-3: Handheld TDS Meter with Carrying Case
With its rugged design and build, the TDS-3 is an ideal meter (tool) that can be used for any application; Ranging from water purification, to hydroponics to industrial waste water treatment. It comes with a black vinyl carrying case, protecting it when carried in a toolbox.

  • Hold Function
  • Auto-off Function (After 10 min.)
  • Built-in digital thermometer
  • Includes a carrying case with belt clip
  • Factory Calibrated with a 342 ppm NaCl solution. (Meter can be recalibrated with a mini-screwdriver).

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Product details
SKU: 3252
Date first available: January 21 2021
Average customer review: 4.2 out of 5 stars 319 customer reviews
Bestsellers Rank: #24 in Measuring Device
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Daniel K


Verified Purchase

October 18, 2021

Plan to start cleaning business made me buy some additional accessories so I can be prepared for almost any situation.
One of first things I had to check was how bad the water in my area was. This is where TDS meter came in.
After researching for the best one and reading many bad comments, inaccuracy and problems people had with other brands I came across HM Digital TDS meter. With only hand full of reviews and recommendations I have decided to go with this one and I have to say I made a right decision. TDS meter might look less modern from others on the market but for me accuracy and reliability is more important than look.
TDS-3 Meter is super simple to use and I can say it is accurate and steady. I have done few test through different days and every test came with almost the same or same readings as previous one. Results are showing up in less than a second and are stable without fluctuation. Temperature mode as well works fast and results are on the screen in matter of seconds which I am glad about as from reading reviews and experiences from other products were showing that a lot of these meters have problem with temperature mode.
HM Meter comes in a nice protective case with pen style clip on and you can keep it in your pocket on your belt or wherever it can fit.

Super satisfied and another great and reliable tool is in my set!

Michel C.


Verified Purchase

January 24, 2018

Fast delivery from this seller, thank you!

I bought this meter based on recommendations from a few Youtubers who test and distill their own drinking water. My rural water is so disgusting, I haven't drunk any since I moved here 8.5 years ago. I don't cook with it or give it to my 2 dogs or my cat. It's horrible and tastes and smells of chemicals and I don't know what else! Instead, I've been buying purified water at a machine outside my grocery store for just 25 cents a gallon. It has no smell or taste. But I was still curious what they would measure on this meter.

As soon as I read the instructions I tested both county water and the purified water. I was SHOCKED that the county was nearly 800ppm of Total Dissolvable Solids! But the purified was just 9ppm! What a difference!



Verified Purchase

March 13, 2021

Having used for several months to test water for fish and also use for exotic strelitzia feeding I am happy with accuracy and consistency.
I also find myself testing all sorts of things from drinking water, bath, beer, rain and have even tested a local swimming reservoir just for interest.
I was sceptical of being useful for long but is still reading near enough the same as when first used on test samples.
Calibration screw is a bonus over digital calibration of the very cheap pens if you have stable solution to reference.
Overall good value if you are looking for a good idea of ppm values but dont need super accuracy or longevity of more expensive units although so far I cant complain about either.

Canadian Amazon Customer


Verified Purchase

It works

February 17, 2022

I can't attest to the absolute accuracy as I haven't checked mine for calibration.
I got it to keep tabs on my hot tub.
With a fresh refill of water plus the right amount of bromine it reads around 260 ppm which is where it should be. Was very high before the change 1,910 ppm.
Quite happy with it as it will give me a heads up as to when to change out the water even though the tub full was still clear even with the high reading.

Amazonian customer


Verified Purchase

November 16, 2022

This tds metre is really easy to calibrate using amy known ppm liquid. Handy little screw on back can finely adjust to any required ppm. Tap water here is 279 ppm, but calibration liquid can be bought. I've bought others before of a different brand and the accuracy was way out even after calibration. I did have to adjust this HM metre slightly by 25pom but was simple to do. Will buy again as and when needed.

Cherry Ann White


Verified Purchase

April 15, 2022

This is a basic tool for measuring total dissolved solids in water and will not give you a water quality indication, however what is does is give you a water hardness figure. If you use a water filter to clean windows or a car, this is a must to determine if the filter substrate / material needs replacing.

It is great for this purpose and a reasonable price.

Pete C.


Verified Purchase

December 11, 2021

Seems accurate enough, I check calibration solution every now and again and is always ok.

To convert to EC ms/cm²... times your meter reading by 2 and then divide by 1000. So if this meter is reading 1450 ppm, do 1450 x 2 = 2900, then 2900 ÷ 1000= 2.9 EC ms/cm²

Get yourself some 342 ppm calibration fluid, it's not expensive.



Verified Purchase

May 24, 2022

These are dead simple to use, and you get an instant repeatable result.
Don't be dumb enough to immerse the whole thing in water though. I did. Then it stopped working.
I bought another one. OK?
Remember to watch the skies! Flying saucers really are real. Don't say you weren't told!



Verified Purchase

Back lit display would make it easier to read numbers

January 08, 2023

Problem is with delivery service nothing wrong with product so far
Keep leaving my packages in the lobby where the public has access without keys and not notifying me that its there i lost a 125 bucks Thursday before new year’s because package disappeared



Verified Purchase

Works well.

December 26, 2021

Tested it with:
Distilled water: 0 ppm.
Bottled RO water: 24 ppm (label said <35 ppm).
Bottled spring water: 129 ppm (label said 222 ppm).
Tap water after RO: 20 ppm.
Tap water: 169 ppm.
Calibration solution (NaCl 342 ppm): 347 ppm.

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