Description
Digital TDS Meter Pen – Water Quality Tester (PPM)
Quickly check the dissolved solids (TDS) in your drinking water, aquarium, or reverse osmosis (RO) system with this easy-to-use digital TDS meter pen. Ideal for diagnosing filter performance, spotting when cartridges need replacement, and verifying RO water quality at home or on-site.
- Fast, accurate TDS readings in ppm (mg/L) with ATC
- Backlit display, Data Hold, Auto Power-Off
- Perfect for RO systems, aquariums, hydroponics & coffee/kettles
- 12-month warranty with local support in Ireland
- Ships from Dublin | Tool-light operation
Why choose this TDS meter
- ✔ Fast, accurate readings in seconds (PPM/ mg/L)
- ✔ Auto calibration & ATC (Automatic Temperature Compensation) for reliable results
- ✔ Hold & backlit display for easy reading in low light
- ✔ Pocket-sized with protective cap for everyday carry
- ✔ Perfect for RO systems to confirm membrane performance and filter change timing
Best for
- • Monitoring reverse osmosis output and knowing when to replace filters
- • Checking tap vs. filtered water quality improvement
- • Aquariums & hydroponics water management
- • Coffee & kettle limescale prevention tests
How to use
- Remove cap and turn the meter on.
- Immerse the probe in a clean sample cup of water (do not exceed the max immersion line).
- Gently swirl and wait 3–5 seconds for the reading to stabilise.
- Press HOLD to lock the reading if needed; record your result (PPM).
- Rinse the probe with distilled/RO water and replace cap.
Tip: For RO systems, compare tap water TDS to RO output. A healthy RO membrane typically reduces TDS by >90%.
What’s in the box
- Digital TDS meter pen (with protective cap)
- Pre-installed batteries
- Quick start guide
Technical specifications
- Measurement range: 0–9,999 ppm (mg/L)
- Resolution: 1 ppm
- Accuracy: ±2% F.S. (typical)
- Temperature compensation: ATC
- Functions: Backlight, Data Hold, Auto Power-Off
- Power: Button cell batteries (included)
Care & calibration
Rinse the probe with RO or distilled water after each test and store dry with the cap on. For best accuracy, calibrate periodically using a TDS/NaCl calibration solution.
Get the most from your TDS readings
If your TDS is high, a Reverse Osmosis (RO) system can dramatically improve taste and purity. Explore compact under-sink RO options with professional installation support.
Warranty & support
- 12-month limited warranty
- Expert local support in Ireland
- Need help choosing or interpreting readings? Browse drinking water systems or contact our team.
Frequently asked questions
What is a “good” TDS reading for RO water?
As a rule of thumb, RO output is often under 50 ppm and at least 90% lower than your tap water. Actual values vary by feed water and membrane age.
Does this meter measure hardness (limescale)?
It reads total dissolved solids in ppm, not hardness directly. However, higher TDS often correlates with higher hardness. For hardness, use a dedicated hardness test or softener.
Can I use it for aquariums?
Yes. It’s widely used in aquatics and hydroponics to maintain stable water parameters.
How often should I calibrate?
For home use, every few months is typical. Calibrate more frequently with heavy use or critical applications.
