How To Check Water TDS At Home? 3 Easy Methods You Should Know

Water quality is a major concern in India, especially with increasing pollution and contamination in water sources. One of the key indicators of water purity is Total Dissolved Solids (TDS). If you’ve ever wondered how to check your water’s TDS at home, you’re in the right place.

In this guide, we’ll explain:
✔ What TDS is and why it matters
✔ Safe TDS levels for drinking water
✔ 3 simple methods to check TDS at home
✔ How RO purifiers help maintain ideal TDS

By the end, you’ll know exactly how to ensure your drinking water is safe for consumption.

How To Check TDS At Home

1.      What Is TDS

2.      Why Should We Check The Water TDS Level

3.      Major Substance Causing High TDS Level In Water

4.      How TO Calculate Water TDS At Home

4.1. How To Check Water TDS Using Digital TDS Meter?

4.2. How To Check Water TDS Using Filter Paper & A Scale

4.3. How To Check Water TDS Using Electrical Conductivity

5.     How Much Water TDS Is Suitable For Consumption

6.     Is 200 TDS Water Safe For Drinking?

7.    What Is the Difference Between TDS And Hardness?

 

What Is TDS?

TDS (Total Dissolved Solids) refers to the combined content of all organic and inorganic substances dissolved in water. This includes minerals, salts, metals, and other impurities. Since water is a natural solvent, it absorbs these substances from soil, pipes, and industrial waste.

Common Substances Contributing to High TDS

• Essential Minerals: Calcium, Magnesium, Potassium
• Harmful Contaminants: Lead, Arsenic, Fluoride, Chlorine
• Industrial Pollutants: Pesticides, Herbicides, Sulfates

While some minerals (like calcium and magnesium) are beneficial in small amounts, excessive TDS can make water unsafe.

Why Should We Check The Water TDS Level?

The Bureau of Indian Standards (BIS) and World Health Organization (WHO) recommend:

• Ideal TDS: 50-150 mg/L
• Permissible TDS: Up to 500 mg/L
• Unsafe TDS: Above 900 mg/L

Effects of High TDS Water

✔ Bad Taste & Odor – High mineral content makes water salty or metallic.
✔ Health Risks – Excess fluoride, lead, or arsenic can cause long-term diseases.
✔ Appliance Damage – Limescale buildup in RO systems, kettles, and pipes.

Effects of Low TDS Water

✔ Flat Taste – Lack of essential minerals affects flavor.
✔ Mineral Deficiency – Extremely low TDS (<50 mg/L) may lack beneficial minerals.

Pro Tip: If your TDS is too high, an RO purifier can help. If it's too low, consider a mineral-enhancing RO system or TDS controller.

3 Easy Methods to Check Water TDS at Home

1. Using a Digital TDS Meter (Quick & Accurate)

A digital TDS meter is the easiest way to check TDS instantly.

Steps to Use a TDS Meter:

1. Remove the protective cap and turn it ON.
2. Dip the meter into the water (up to the marked immersion level).
3. Stir gently to remove air bubbles.
4. Wait 10-15 seconds for a stable reading.
5. Note the value (in ppm or mg/L).
6. Rinse and dry the meter after use.

Note: Some meters multiply readings by 10 (e.g., 100 ppm = 1000 ppm). Check the manual.

Precautions:

• Do not submerge beyond the max level.
• Avoid direct sunlight exposure.
• Calibrate periodically for accuracy.

 

2. Using Filter Paper & Scale (Traditional Method)

This method is useful if you don’t have a TDS meter but requires more effort.

What You Need:

✔ Clean glass container
✔ Filter paper or cotton layers
✔ Evaporating dish
✔ Weighing scale
✔ Pipette (for 50ml sample)

Steps:

1. Weigh the empty evaporating dish (B).
2. Filter 50ml water through filter paper into the dish.
3. Let the residue dry completely.
4. Weigh the dish again with residue (A).
5. Calculate TDS:

Formula:
TDS (mg/L) = (A – B) × 1000 / Water Sample (ml)

Example:

• If (A – B) = 25 mg and water sample = 50ml

TDS = (25 × 1000) / 50 = 500 mg/L

 

3. Using Electrical Conductivity (For Advanced Users)

Since dissolved salts conduct electricity, a conductivity meter can estimate TDS.

Steps:

1. Dip the conductivity probe into water.
2. Wait for a stable reading (in µS/cm).
3. Convert to TDS using:

Formula:
TDS (mg/L) = 0.67 × Conductivity (µS/cm)

Example:

• If conductivity = 500 µS/cm
• TDS = 0.67 × 500 = 335 mg/L

Note: The factor (0.55–0.8) varies with temperature and impurities.

3. Using Electrical Conductivity (For Advanced Users)

Since dissolved salts conduct electricity, a conductivity meter can estimate TDS.

Steps:

1. Dip the conductivity probe into water.
2. Wait for a stable reading (in µS/cm).
3. Convert to TDS using:

Formula:
TDS (mg/L) = 0.67 × Conductivity (µS/cm)

Example:

• If conductivity = 500 µS/cm
• TDS = 0.67 × 500 = 335 mg/L

Note: The factor (0.55–0.8) varies with temperature and impurities.

What Is the Ideal TDS Level for Drinking Water?

   

TDS vs. Hardness: What’s the Difference?

 

How RO Systems Help Control TDS

If your water TDS is high, an RO water purifier can effectively reduce it. Here’s how:

✔ Removes 90-95% dissolved impurities
✔ Adjustable TDS settings (via TDS controller)
✔ Retains essential minerals (in advanced RO systems)

Need help?

• RO installation/uninstallation – Get professional setup.
• RO repair – Fix leaks, low pressure, or taste issues.
• RO AMC – Regular servicing ensures optimal performance.

Final Thoughts

Checking your water’s TDS is crucial for ensuring safe drinking water. While a digital TDS meter is the easiest method, filter paper and conductivity tests also work.

If your TDS is too high, consider an RO purifier. For maintenance, opt for an RO AMC to keep your system running smoothly.