

💧 Measure purity like a pro—because your water quality deserves precision.
The HM Digital TDS-3 is a handheld Total Dissolved Solids meter offering a wide 0-9990 ppm measurement range with 1 ppm resolution and ±2% accuracy. Designed for commercial and professional use, it features a large LCD screen displaying both TDS and temperature, a hold function for saving readings, and comes with a durable carrying case with belt clip. Powered by included LR44 batteries, it delivers reliable, instant water quality testing for applications from filtration systems to hydroponics.
| ASIN | B000VTQM70 |
| Additional Features | High Accuracy |
| Age Range (Description) | Adult |
| Age Range Description | Adult |
| Battery Life | 3 Hours |
| Best Sellers Rank | #2,074 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #1 in Conductivity Meters & Accessories |
| Brand | HM Digital |
| Brand Name | HM Digital |
| Color | Style 1 |
| Customer Reviews | 4.6 out of 5 stars 1,741 Reviews |
| Display Type | LCD |
| Global Trade Identification Number | 00826333000001 |
| Included Components | Carrying case |
| Indoor Outdoor Usage | Indoor |
| Item Length | 1 Inches |
| Item Weight | 0.2 Grams |
| Manufacturer | HM Digital |
| Model | TDS-3 |
| Model Name | TDS-3 |
| Number of Batteries | 2 LR44 batteries required. (included) |
| Outer Material | Metal |
| Part Number | TDS-3 |
| Power Source | Battery Powered |
| Product Care Instructions | Wipe Clean |
| Resolution | 1 ppm |
| Reusability | Single Use |
| Special Feature | High Accuracy |
| Style Name | Contemporary |
| UPC | 891144000083 826333000001 |
| Unit Count | 1.0 Count |
| Upper Temperature Range | 50 Degrees Celsius |
J**Y
Perfect tester
I bought the iSpring tester first because it's a known brand. However it was defective when opened the box. Ordered this one instead, it's working as a charm and build quality also exceeded the iSpring by a mile. I recommend this product to anyone who's looking for a water tester affordable and accurate.
D**S
Good, simple, efficient!
Surprisingly helpful and easy to use! We just care about PPM (aka TDS) related to the Reverse Osmosis (RO) filter system we just installed, and this little guy does the trick. Inexpensive and working great for us for 2 weeks now!
J**N
Cheap but worksahic
This thing is so cool! It's so cheap compared to the alternatives and it is accurate upon arrival. I use it like a lab master and despite all the rough use it's still working.
D**N
Accurately calibrated
What makes this tester stand out against many others: it has adjustable calibration and is calibrated at the factory. I have checked the readings against the reference solution and the calibration is accurate. The build quality is solid as well.
A**1
Great for quick checks, very easy to use
I’ve been using this to monitor my RO system and aquarium water. It’s incredibly straightforward—just dip it in and you get a reading instantly. The build quality feels decent for the price, and the battery life has been impressive so far. My only minor issue is that it doesn't come with calibration fluid, so you have to trust the factory settings or buy extra supplies to be 100% sure of the accuracy. Overall, a must-have for the price.
M**E
Great TDS Meter for Hydroponics – Easy to Use & Accurate!
I’ve been using the HM Digital TDS-3 for my hydroponic system, and it’s been a game-changer. If you’re serious about growing healthy plants, keeping track of your nutrient levels is crucial, and this little device makes it incredibly easy. What I Like: ✅ Accurate & Reliable – The readings are consistent, and the 0–9990 ppm range covers all my needs. I can easily check if my nutrient solution is too strong or too weak. ✅ Temperature Compensation (ATC) – I don’t have to worry about temperature affecting the accuracy. The meter adjusts automatically. ✅ Super Easy to Use – Just dip it in, wait a couple of seconds, and get an instant reading. The hold function is great for locking the number so I can check after pulling my hand out of my reservoir. ✅ Compact & Battery-Saving – It’s small, comes with a protective case, and has an auto shut-off to save battery life. A Couple of Things to Keep in Mind: ❌ Not Waterproof – Be careful not to drop it in water. I make sure only the probes are submerged. ❌ Doesn’t Measure pH – This is strictly for TDS and temperature, so you’ll need a separate pH meter. Final Thoughts: For the price, this TDS meter is absolutely worth it. It gives me quick, accurate readings and helps me dial in the perfect nutrient levels for my plants. If you’re into hydroponics, aquaponics, or even just checking your water quality, I highly recommend it!
K**Z
It works, seems to be accurate, and is low cost
I tested this with my tap water and filtered water from the fridge. It comes calibrated from the factory, but not sure how long the calibration will last. The measurements were easy to read and matched the report from our water company when testing tap water, and it correctly reported that the hardness value was lower when testing filtered water, so it seems this device works well. I'm happy with it and glad I got it, especially for the low price.
B**Y
Great quality
Great price. Great quality Love ot
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2 months ago
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