How to Use Xiaomi Water Tester: A Complete Guide from Calibration to Results Analysis

Xiaomi water tester (most often Mi model) TDS Pen or ClearGrass TDS Meter, which is branded as an ecosystem, has become an indispensable tool for drinking water professionals, and this compact instrument measures the level of total mineralization (TDS) — And this is a key indicator that tells you how good water is for drinking, cooking, or even watering plants, but how do you use it to get accurate data? From unpacking to interpreting the results, and also reveal the secrets that the manufacturer does not always indicate in the instructions.

Many people mistakenly think that Xiaomi tester shows the purity of water or the presence of harmful impurities. It actually measures electrical conductivity, which depends on the concentration of dissolved salts, metals and minerals. For example, water after reverse osmosis will show a value close to 0, and mineral - from 200 to 1000 mg / L. But how to distinguish useful minerals from harmful minerals? And why sometimes the device lies? The answers are lower.

What is it? TDS And why is it important?

abbreviation TDS (Total Dissolved Solids translates to "total dissolved solids." This is the sum of all inorganic and organic particles that have passed through the filter with 2 microns of pore. In a household tester, Xiaomi measures in mg/l (ppm) - milligrams of matter per liter of water.

Why is this critical to your health? It's simple.

• 💧 0-50 mg/l is almost distilled water, suitable for aquariums, but not for constant drinking (washes minerals from the body).
• 🍶 50 to 150 mg/l is the ideal range for drinking water, and these are good mineralized reverse osmosis filters.
• 🏔️ 150-300 mg/l is medium hardness. The taste of the water can be "metallic", there may be deposits in the kettle.
• ⚠️ Over 1000 mg/l - water is unfit for drinking without purification, often found in wells or old water pipes.

But there is a catch: the Xiaomi tester does not distinguish between useful minerals (calcium, magnesium) and harmful (lead, nitrates). TDS 500 mg/l can be useful, and tap water with the same index, contain rust and heavy metals. TDS-A meter is just the first step in water analysis.

Tester kit and device: what's inside the box?

In the standard kit of the Xiaomi Mi tester TDS Pen (or its analogues, for example, ClearGrass) TGD-1) enter:

• 📦 The device itself in a protective case (sometimes with a clip for fastening to the belt).
• 🔋 2 type batteries LR44 (Some models are already installed).
• 📄 Brief instruction in Chinese/English (Russian is often absent).
• 💧 Calibration solution (rarely found, usually sold separately).

On the body of the device are located:

1. The screen shows the value TDS in mg/L (ppm) and water temperature (in some models).
2. On/calibration button – 3 seconds hold on/off the device.
3. The sensor is the metal plates at the bottom that are submerged in water.
4. Charge indicator – flashes at a low level of the battery.

Important: Xiaomi's tester sensor is covered with a thin layer of protective coating that wears off over time. Don't rub it with hard sponges, it will lead to inaccurate readings. Use soft cloth moistened in distilled water to clean.

💡

If the test screen shows ERR Or flashes, try replacing the batteries -- even if they're new.

Step-by-step: how to use the Xiaomi water tester

The algorithm is simple, but there are nuances that affect the accuracy of the measurements.

Now, more details about each step:

1. Turn on: press and hold the button for 3 seconds. ON, then TDS The device will automatically turn off after 2 minutes of inactivity.
2. Water preparation: If you're testing tap water, first drain it for 1-2 minutes, and that's going to get the stagnant water out of the pipes. For bottled water, just shake the bottle.
3. Immersion of the sensor: lower the device into water to a depth of no more than 5 cm Do not touch the bottom or walls of the container with the sensor - this will distort the readings.
4. Take a reading: wait until the numbers on the screen stop changing (usually 5-10 seconds) if the values "jump", the water is too contaminated or the sensor is contaminated.

Professional life hack: for accuracy, take 3 consecutive measurements and take the average. For example, if the device showed 180, 185 and 178 mg / l, the final result is: TDS ≈ 181 mg/l.

Tester calibration: when and how to do it?

Sizing is required if:

• 🔄 New device (manufacturer recommends calibration before first use).
• ⚠️ Indications are very different from the reference (for example, distilled water shows not 0-10 mg / l).
• ⏳ It’s been over 6 months since the last calibration.

For calibration, you will need a standard solution with a known TDS (It is usually 342 mg/L or 1413 mg/L. It can be bought alone or prepared independently (recipe below:

1. Turn the device on, load the sensor into the calibration solution.
2. Hold the button for 10-15 seconds until the screen says CAL.
3. Wait until the screen is finished (the screen will flash and show you) OK).
4. Wash the sensor with distilled water.

💡

Without calibration, the tester error can reach ±10%, for example, in the real world. TDS 200 mg / l the device will show 180 to 220 mg / l.

If you can’t buy a solution, you can prepare it at home:

⚠️ Warning: Homemade solution is less accurate than factory solution. For critical measurements (e.g. aquarium water), use certified standards.

Decoding the results: what to do if TDS too high?

You got the tester readings -- what's next?

Examples from life:

• 🚰 Tap water in Moscow: usually 150-250 mg / l (depending on the area).
• 💧 Filtered water (Brita jug): 80–120 mg/l.
• 🏔️ Essentuki mineral water-17": 1000–1400 mg.
• 🌿 Water for orchids: not higher than 100 mg / l (otherwise the roots rot).

If your tester showed TDS above 300 mg/L, check:

1. The condition of the pipes (rust, old metal pipes).
2. Filter operation (it may be time to replace the cartridge).
3. Water source (wells may contain excess iron or salts).

⚠️ Note: If after the reverse osmosis filter TDS above 50 mg/L, which is a sign of malfunctioning membrane!

Frequent Mistakes and How to Avoid Them

Even experienced users sometimes make mistakes that distort the results.-5 slip-up:

• 🚱 Measurement directly from the tap: water in the pipes stagnates, especially at night. Always drain it 1-2 minutes before the test.
• 🧴 Dirty sensor: residues of soap, fat or salts on the sensor give false readings.
• ⚡ Batteries discharged: low charge, the device can show low values. Change the batteries every 6 months.
• 🌡️ Ignoring temperature: TDS Most Xiaomi testers will automatically compensate for this, but if your model doesn’t support the function, measure at 25.°C.
• 🧂 Testing of carbonated water: bubbles CO₂ Shake the bottle before measuring it and let the gas escape.

Another common problem is that the tester shows 0 mg/l in any water.

1. Broken sensor (check the integrity of metal plates).
2. Oxidation of contacts of batteries (clean them with a cotton swab with alcohol).
3. Factory marriage (if the device is new, contact Xiaomi service).

💡

If the tester suddenly stopped working, try to "reset" it: remove the batteries for 5 minutes, then insert back in. This helps with software failures.

Care and storage: how to prolong the life of a tester?

The device will last for years if you follow simple rules:

• 💦 After use: rinse the sensor with distilled water and dry in air (do not wipe with cloth!).
• 🔋 Batteries: Remove them if you don't use the appliance for more than a month.
• 🌡️ Storage temperature: from -10°C +50°C. Do not leave the tester in the sun or near heaters.
• 🚫 What to avoid: Immersion of the sensor in aggressive liquids (vinegar, acids); impacts or falls (sensor brittle!); use in salty seawater (will lead to corrosion).

If the sensor is contaminated, clean it like this:

1. Prepare the solution: 1 part vinegar to 3 parts water.
2. Load the sensor for 10 minutes.
3. Rinse with distilled water.
4. Dry for 12 hours before use.

⚠️ Warning: Never use abrasive cleaning products (baking soda, sand) – they scratch the sensor, leading to inaccurate readings.

FAQ: Answers to popular questions