- HM Digital Pro COM-300 Meter
- 2 x AAA Batteries
- Lanyard
HM Digital Pro COM-300 pH TDS EC Temp Meter
starting from 0% interest financing from
/mo.
- Tracks 5 water quality metrics at once with professional 0.1 pH resolution
- Replaceable sensors and platinum electrodes extend the service life of the hardware
- IP-67 waterproof rating prevents damage if the unit falls into a nutrient tank
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We support operations & licensed facilities with volume pricing, dedicated account managers, and custom equipment consultation.
Who This Is For
- You are upgrading to an all-in-one meter because juggling separate pens for pH and EC makes daily checks a chore.
- You are moving to digital calibration because manual trimming of analog screws is too imprecise for nutrient mixing.
What We Found
- The IP-67 rating is the real winner here since most handhelds die the first time they take a swim in the tank.
- We suggest keeping a spare probe on hand so a broken glass sensor does not stop your mixing for the week.
- The non-linear conversion factors for EC to TDS provide a more accurate picture of actual nutrient concentration.
What Users Say
- Growers who moved to this all-in-one unit say they stopped losing time hunting for three different pens every morning.
- Operators working in wet environments report the screen stays clear while cheaper meters often fog up internally.
- Users managing large reservoirs say the digital calibration makes it much easier to trust their daily readings.
HM Digital Pro COM-300 pH TDS EC Temp Meter
Maintaining precise water quality is the cornerstone of a successful harvest. The HM Digital Pro COM-300 is a professional-grade, multi-parameter meter designed to give hydroponic growers and laboratory technicians absolute control over their nutrient solutions. By tracking pH, EC, TDS, salinity, and temperature in one portable device, you can ensure your plants are always in the optimal environment for growth.
Compared to other models like the HM Digital Pro COM-100, the COM-300 adds critical pH monitoring capabilities, making it a truly all-in-one solution. This waterproof device features a large, easy-to-read LCD screen and digital calibration for professional accuracy. Whether you are managing a complex hydroponic system or conducting sensitive lab tests, this meter provides the reliability you need.
As part of the world-renowned HM Digital collection, the COM-300 is built for durability with an IP-67 waterproof rating and replaceable sensors. For growers who only require specific measurements, we also offer the HM Digital Pro PH-200 for dedicated pH testing. Elevate your gardening precision with a tool that combines five essential metrics into a single, rugged handheld unit.
What's Included
Features
🌍
Variable Applications
Perfect for testing water in hydroponics, water treatment, and laboratory usage.
📱
Easy to Read
Large LCD screen makes checking your parameters quick and effortless.
🍃
Energy-Saving
Automatic shut-off feature preserves battery life when the meter is idle.
🔋
Battery Operated
Runs conveniently on a pair of standard AAA batteries for maximum portability.
Specifications
| Specification | Value |
|---|---|
| pH Range | 0 – 14 pH (0.1 pH resolution) |
| EC Range | 0 – 9990 µS; 0 – 9.99 mS |
| TDS Range | 0 – 8560 ppm (0.7 Scale); 0 – 5000 ppm (0.5 Scale) |
| Temperature Range | 0-55 °C; 32-130°F (0.1 °C/°F resolution) |
| Accuracy | +/- 2% |
| Conversion Factor | Non-linear for KCl, 442TM, or NaCl |
| Probe | Detachable platinum electrodes & pH glass sensor |
| Housing | IP-67 Waterproof (submersible and floats) |
| Power Source | 2 x AAA (included) |
| Dimensions | 18.5 x 3.4 x 3.4 cm (7.3 x 1.3 x 1.3 inches) |
| Weight | 101.5g (3.6 oz) |
FAQs
What parameters does the COM-300 measure?
The COM-300 is a 5-in-1 tool that measures pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Salinity, and Temperature.
Is the COM-300 waterproof?
Yes, it is IP-67 rated, meaning it is fully waterproof, submersible, and designed to float if dropped into a reservoir.
Can I replace the sensor on this meter?
Yes, the COM-300 features replaceable sensors, allowing you to maintain the unit for years without needing to replace the entire device.
Does it come with everything needed to start?
The package includes the meter and 2 x AAA batteries. For pH testing, we recommend having calibration solutions on hand to ensure ongoing accuracy.
What is the difference between this and the COM-100?
The COM-300 includes pH measurement capabilities, whereas the COM-100 only measures EC, TDS, and Temperature.
Happy To Help
Questions About This Product?
Our specialists are happy to help. Call us or send a message and we'll get back to you within one business day (most of the time within a few hours.)
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