How to Remove Total Dissolved Solids from Drinking 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 road salts, and chemicals or fertilizers from farms.

TDS most commonly refers to the levels of dissolved ions in your water, like calcium, magnesium, potassium, sodium, and nitrates. They naturally occur in water after it filters through bedrock and soil. A certain amount of dissolved solids in water is normal and even beneficial, but problems start when levels of TDS increase beyond what would accumulate naturally.

Why Do you Need to Measure Total Dissolved Solids?

Testing the water is a great way to check the quality of the water you receive and use for different purposes. Here are some reasons why you need to measure TDS in water.

  • Taste – High levels of TDS in water affect the taste of your drinking water. Depending on the type of dissolved solids in the water, your water can taste bitter, salty, or sulfurous.
  • Health Purposes – High TDS water is completely safe to drink. However, some substances such as lead or copper can lead to health hazards.
  • Filter Maintenance – Water filtration systems are adversely affected by a high TDS. Regular testing of water purification systems ensures that the filters are working properly
  • Cooking – While high TDS levels are not harmful to health, they can alter the flavor of your food.
  • Cleaning – A high TDS in water leaves ugly stains on your utensils. This type of water also fades the color of your clothes, causing a buildup in your sinks, tubs, and faucets.
  • Plumbing and Appliances – High levels of dissolved calcium and magnesium salts can cause limescale build-up in pipes and appliances, shortening their lifespan. The above reasons are the reasons for measuring total dissolved solids in water.

Why do you Need to Measure TDS?

The water you receive exceeds the maximum level of TDS that must be present in the water. Water with a TDS content of more than 1000 mg/l is not suitable 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 level of TDS in the water. However, the presence of toxic ions such as lead, nitrate, cadmium, and arsenic in water can lead to a number of serious health problems. This is particularly important for children, as their immune system is not yet fully developed and they are much more sensitive to pollutants.

How to Remove Total Dissolved Solids From Drinking Water

TDS Water Levels

Wondering how your water’s TDS level compares to others? The table below provides different ranges of TDS, and whether they’re safe for drinking.

TDS level in mg/LIndication
Less than 50Safe to drink, but lacking essential minerals
50-150Acceptable to drink
150-250Good to drink
250-350Acceptable to drink, but water could contain dangerous impurities
350-500Not acceptable to drink, water should be filtered
500-900Not safe to drink, water should be filtered
900-1200Least acceptable to drink, avoid drinking this water
1200-2000 or aboveVery high TDS, dangerous to drink

How to Remove Total Dissolved Solids from Drinking Water?

Now we’re refreshed on the basics of total dissolved solids (TDS), let’s look at the best ways to remove TDS from your drinking water.

Method 1: Treating TDS With Reverse Osmosis Filtration

Reverse osmosis (RO) water filtration systems are generally the most efficient and effective way to remove TDS, and their negative effects, from your water. Reverse osmosis drinking water systems typically contain a semipermeable membrane that separates the water from dissolved solids.

RO water purifiers can remove most TDS, including dissolved salts, minerals, and dangerous chemicals, down to 0.0005 microns small.

These systems are often installed at the point of use, like under the kitchen sink or hooked up to an icemaker or refrigerator’s cold-water dispenser. Typically, water first flows through a prefilter to remove larger sediment like sand and then through an activated carbon filter, which reduces chlorine taste and odor. Look for a system certified by a third party such as the Water Quality Association.

Method 2: Distillation

Distillation is another effective means of removing inorganic and organic substances from drinking water. The distillation process involves boiling water until it evaporates. The water then travels along a cool surface before condensing into a separate container.

The majority of contaminants have higher boiling points than water, so they remain in solid or liquid form at the bottom of the boiling solution in the boiling chamber. They’re then removed when the chamber is cleaned between uses.

Any TDS that are able to evaporate and condense with water are removed by a carbon filter, which sits in the spout of the distiller, trapping contaminants as water drips into the container.

A distiller essentially acts as a drinking water purifier, removing the majority of TDS. However, it takes hours to produce a single batch of distilled water, and not everyone has the patience to wait that long.

Method 3: Deionization

Deionization involves sending water through positive and negative electrodes. This causes the positive ions to break off from the water and be attracted to the negative electrode.

De-ionized water is highly pure because most of its positive and negative ions have been removed. However, deionization doesn’t target non-ionic contaminants, so water is usually treated with RO before this process to reduce TDS to a permissible range. For this reason, deionizers aren’t considered water purifiers, and they’re not as effective as other methods.