What are Total Dissolved Solids (TDS) & How to Reduce Them?
The drinking water that we get today is flushed with hazardous chemicals from the different water treatment plants. As a result, the natural minerals present in water are taken away. In such a situation, it is essential to use the proper filtration processes to remove the contaminants and make water safe for consumption. The main contaminant present in water is total dissolved solids (TDS) left in the water after the normal filtration process. Contaminants that are larger than 2 microns are termed total dissolved solids. A fine filter generally removes particles that are 0.45 microns in size and originates from different sources. After the filtration process, the remaining contaminants in water consist of charged atoms and ions. Moderate to high TDS in water not only changes the taste of water but also poses a lot of health hazards. One of the most effective ways to maintain the TDS level is by using the leading RO water purifier in India. In this blog, we discuss in detail the ways to remove excessive TDS present in water.
What is TDS in Water?
Total Dissolved Solids (TDS) in water are some organic and inorganic materials, which include minerals and ions that are dissolved in a particular quantity in water. When water passes through stones, pipes, or different surfaces, the particles are absorbed into the water. TDS in water can come from different sources such as minerals in chemicals used for treating water, runoff from the road salts, and chemicals or fertilizers from the farms. Calcium, Magnesium, Sodium, and Potassium cations, as well as Carbonate, Hydrogen Carbonate, Chloride, Sulfate, and Nitrate anions, are commonly the most prominent constituents.
Why Do you Need to Measure Total Dissolved Solids?
Testing the water is a great way to check the quality of water that you receive and use for different purposes. Here are some reasons you need to measure TDS in water.
- Taste- High levels of TDS in water affect the taste of your drinking water. Your water may taste bitter, salty or sulfuric depending on the type of dissolved solids present in water.
- Health Purposes- Water with high TDS is completely safe to drink. However, some substances such as lead, or copper can lead to health hazards.
- Maintenance of Filters- Water filtration systems are affected by a high level of TDS. Testing the water purifier systems regularly will ensure that the filters work properly
- Cooking- Though high TDS doesn’t affect health, it can alter the taste of your food.
- Cleaning- High TDS in water leaves ugly spots on your utensils. This type of water also fades the color of your clothes, leading to a buildup in your sinks, tubs, and faucets.
- Plumbing and Appliances- High amounts of dissolved calcium and magnesium salts can cause scale to form in pipes and appliances, reducing their lifespan. The above are the reasons to measure total dissolved solids in water.
Why do you Need to Measure TDS?
The water that you receive exceeds the maximum level of TDS that needs to be present in water. Water that has a TDS level of more than 1000mg/L is unfit for consumption. A high level of TDS in water can lead to a number of health problems. The presence of potassium, sodium, and chlorides increases the TDS level in the water. However, the presence of toxic ions such as lead, nitrate, cadmium, and arsenic present in water can lead to a number of serious health problems. This is especially important for children because they are much more sensitive to contaminants because their defense systems have not fully developed. The purer the water, one can be assured of good health. KENT provides one of the best water purifiers in India that come with a TDS controller to ensure that the water you drink is safe for consumption.
TDS Level Chart for Drinking Water
One of the important questions that many people have in their minds what is the acceptable TDS level in the water. To help you out, we are listing two tables that discuss the palatability quotient and acceptable TDS level.
TDS Level in parts per million(ppm) | Palatability Quotient |
Between 50-150 | Excellent for drinking |
150-250 | Good |
250-300 | Fair |
300-500 | Poor |
Above 1200 | Unacceptable |
Is low TDS water harmful to Human Body?
TDS present in water is not a measure of any single contaminant and so is generally not regulated as a health issue by many government agencies. A high TDS level, however, can affect the taste and odour of water. The Environmental Protection Agency in the US has set the maximum recommended level of 500 milligrams per litre (mg/L).
The TDS level in water can be determined with the help of a TDS meter. A TDS test helps determine the total amount of dissolved solids present in water. However, it doesn’t identify any individual compounds or the sources. As a result, it is essential to conduct some additional tests to determine the contaminants present in water.
Moreover, one can determine if the TDS level in water is healthy or bad for the body based on the sort of salts and compounds released in it. TDS is made up of a variety of salts, minerals, and organic compounds, including Calcium, Chlorides, Sulfates, Magnesium, Potassium, Carbonates, and Bicarbonates, among others. While some of these may supply a few minerals to the body, the most are deemed hazardous and must be filtered before being consumed.
How Much TDS Level in Water Good For Health
The table mentioned below provides a permissible range of TDS in drinking water and reasons why the TDS level mentioned in water is not acceptable for drinking:
TDS Level (Milligram/Litre) | Remarks |
Less than 50 | Unacceptable as it lacks essential minerals |
50-150 | Acceptable for drinking. The TDS level is ideal for areas where the water polluted by sewage or industrial waste |
150-250 | Good. The water is ideal for people with cardiovascular disease |
250-350 | Good. The water is ideal for people with cardiovascular disease |
350-500 | Fairly acceptable |
500-900 | Less acceptable |
900-1200 | Least acceptable. Avoid drinking water that has a TDS level of 900 |
1200-2000 | Water is not acceptable for drinking. |
Above 2000 | Unacceptable |
According to the Bureau of Indian Standards (BIS), the upper limit of TDS levels in water is 500 ppm. The TDS level recommended by WHO, however, is 300 ppm.
Ways to Reduce or Remove TDS in Water
TDS is reduced in the same way that Salt, Calcium hardness, Nitrates, and Cyanuric Acid are reduced. Read on for more details.
1. Reverse Osmosis (R.O.)
Reverse Osmosis removes TDS by forcing the water, under pressure, through a synthetic membrane. The membrane contains microscopic pores which will allow only molecules smaller than 0.0001 microns to pass through. As the molecules of dissolved metals and salts are large compared to the water molecules, water squeezes through the membrane leaving the metals and salts behind.
2. Distillation
The process involves boiling water to produce water vapor. The water vapor rises to a cool surface where it is condensed back into the liquid form. The dissolved salts are unable to vaporize and remain in the boiling solution.
3. Deionisation (DI)
In this process, water is passed through a positive and negative electrode. The ion-selective membranes enable the positive ions to separate from the water and move towards the negative electrode. The end result is de-ionized water with high purity. However, the water is first passed through a reverse osmosis unit first in order to remove the non-ionic organic contaminants.
So, which Water Purifier is best?
One of the important factors that you need to consider when looking for a water purifier is the TDS level. Depending on the TDS level, you need to decide whether you need an RO, UF, or UV water purifier. To make your work easy, here’s a table that will help you understand which water purifier is ideal for a particular TDS level.
TDS Level | Type of Purifier |
0-200 | UV Water Purifier |
200-300 | RO+UV water purifier |
300-500 | RO+UV+UF |
Areas that receive water with a very high TDS level are recommended to use water purifiers that use a combination of RO+UV/UF with a TDS Controller. The combination of various water purification technologies removes chemical, dissolved as well as physical impurities from water to make it suitable for consumption.
Why Should You Keep a Check on the TDS Level?
Even after passing through a water filter, drinking water may have high TDS, giving it a salty, harsh flavor. Also, there are a number of reasons why you need to check the TDS level in the water. Some of the reasons are:
1. Taste and health
A high TDS level alters the taste of water and makes it salty, bitter, or metallic. High TDS levels also indicate the presence of toxic minerals which is hazardous to health.
2. Hardness
High TDS makes water hard, leading to scale build-up in pipes, dry hair, and spots on utensils, and also makes the kitchen appliances ineffective. Checking the TDS level of water helps you avoid these problems beforehand.
3. Pools and Spas
Pools, as well as spas, need to monitor the TDS level in water constantly to prevent any maintenance problems.
High TDS indicates the existence of harmful substances and pollutants. Hard water is caused by high TDS levels, therefore if you’re using a RO filter, make sure to match it with a water softener to make the water more drinkable.