12th, May, 2025

Why Drinking Water TDS Level Matters – Especially for RO Users

Are you building your dream home and planning your house plan? Then don't forget one essential thing – safe and clean drinking water. In India, most of us rely on water purifiers to remove harmful chemicals, bacteria, and impurities from water. But do you know the TDS level of your water plays a big role in choosing the right water purifier, especially RO (Reverse Osmosis) systems?

In this article, we’ll explain what TDS (Total Dissolved Solids) is, why it matters, and how it affects your water purifier’s performance – all in simple words. Plus, we’ll help you choose the best water purifier for your home in 2025.

What is TDS in Water?

TDS (Total Dissolved Solids) means the amount of minerals, salts, metals, and other solids dissolved in water. TDS is measured in mg/L or ppm (parts per million).

Some common examples of dissolved solids include:

• Calcium

• Magnesium

• Potassium

• Sodium

• Chloride

• Heavy metals (like lead or arsenic in some areas)

Why is TDS Important for Drinking Water?

TDS affects:

• Taste of Water: High TDS can make water taste salty, bitter, or metallic.

• Health: While some minerals are essential, too much or too little can affect your health.

• Water Purifier Efficiency: Knowing your TDS level helps you choose the right RO purifier or UV/UF purifier.

Appliances & Pipes: Hard water (high TDS) can damage washing machines, geysers, and pipelines due to scaling.

Ideal TDS Level for Drinking Water 

as per BIS – Bureau of Indian Standards:

• Below 50 ppm – Not acceptable (too low, lacks essential minerals)

• 50–150 ppm – Excellent

• 150–300 ppm – Good

• 300–500 ppm – Fair (still safe)

• Above 500 ppm – Not recommended (can be harmful over time)

Ideal TDS for RO users: Between 80 to 200 ppm, as RO purifiers remove excess salts while retaining essential minerals (if they have TDS controllers or mineral cartridges).

Dealing with hard water at home? Don’t miss our guide on the Top Water Softener Companies in India.

Why Do You Need a Water Purifier at Home?

Tap or borewell water in Indian homes often contains:

• Bacteria and viruses

• Excess salts and metals

• Pesticides or industrial waste (in some areas)

Using untreated water for drinking or cooking can cause:

• Stomach infections

• Kidney stones

• Long-term health issues

That’s why having a suitable water purifier based on TDS level is important for your family’s health.

Different Types of Water Purifiers

1. RO (Reverse Osmosis) Purifier

• Best for: Areas with high TDS (above 300 ppm)

• How it works: Forces water through a semi-permeable membrane to remove dissolved salts, metals, and impurities.

• Downside: It also removes good minerals unless there's a TDS controller or mineral booster.

2. UV (Ultraviolet) Purifier

• Best for: Low TDS water (below 300 ppm) with microbial contamination
  How it works: Uses UV light to kill bacteria and viruses, but doesn’t remove dissolved salts.

3. Normal/Gravity-Based Filters

• Best for: Municipal water with very low TDS (below 150 ppm)
  How it works: Uses activated carbon and sediment filters; doesn’t need electricity or running water.

Still confused between softeners and purifiers? Learn more in Water Softening vs Water Filtration – Know the Difference.

Why RO Water Users Should Care About TDS

Most people install an RO purifier without checking the source water TDS level. But here's why that matters:

• Too Low TDS After RO = Health Risk
  RO can lower TDS below 50 ppm, which means essential minerals like calcium and magnesium are also removed. This can lead to mineral deficiency over time.

• High Input TDS = RO Necessary
  If your water TDS is above 500 ppm, RO is a must to reduce harmful contaminants like fluoride, arsenic, and heavy metals.

• Low Input TDS = RO Not Required
  If your supply water has TDS under 300 ppm, a UV or UF purifier might be enough, and you don't need RO.

RO vs UV vs Normal Filter – Key Differences

How to Choose the Right Water Purifier for Your Home

Before buying a water purifier, follow these steps:

Step 1: Test Your Water TDS Level

• Use a digital TDS meter (available online or in local stores).

Step 2: Identify the Water Source

• Borewell water? Likely high TDS

• Tanker water? May vary

• Municipal supply? Usually low TDS

Step 3: Choose Based on Water Type

• TDS > 500 ppm → RO purifier (with TDS controller or mineralizer)

• TDS 150–300 ppm → UV purifier

• TDS < 150 ppm → Gravity-based filter

Recommended Water Purifiers for Indian Homes (2025)

Here are some top-performing water purifiers based on water quality:

Also, check out the Top Water Purifier Brands in India to explore trusted names before making a purchase.

 FAQs about Water TDS Level

Q1. What is the safe TDS level for drinking water?

Ideally, between 150–300 ppm. Above 500 ppm is not recommended.

Q2. Can an RO purifier be used with low TDS water?

It’s not advised. RO purifiers remove even essential minerals. Use a UV or gravity-based filter instead.

Q3. How can the TDS level of water be checked at home?

Use a digital TDS meter (available for ₹300–500 online). Dip it in the water, and it shows the reading in ppm.

Q4. Does RO water cause health issues?

Not if used correctly. Just ensure the purifier has a TDS controller or mineral booster to retain good minerals.

Q5. Is bottled water better than RO water?

Not always. Bottled water can be inconsistent. A good home RO purifier with a TDS adjuster is more reliable and economical in the long run.

Conclusion

The TDS level in your water matters a lot – especially if you’re using an RO purifier. Too high, and you risk health problems. Too low, and your RO might remove essential minerals. That’s why understanding your water quality and choosing the right water purifier is key to keeping your family safe and healthy.

Whether you're planning your new house plan or upgrading your existing setup, always test your water first, then buy the best purifier suited for your area. Safe water is not just a choice – it’s a necessity.