Everything You Need to Know About TDS(Total Dissolved Solids)

Water quality depends on its water quality indicators, good drinking water quality should meet the corrsponding national water quality standards.

TDS and water quality are two completely different concepts, TDS is one of the water quality indicators, usually used to measure the quality of pure water, reverse osmosis water systems.

But what is TDS?

TDS stands for Total Dissolved Solid, which refers to the combined content of all inorganic and organic substances dissolved in water. These substances can include:

• Minerals: Calcium, magnesium, potassium, and sodium.
• Salts: Chlorides, sulfates, and bicarbonates.
• Metals: Lead, iron, copper, and arsenic.
• Organic Matter: Compounds from decaying plants or other natural sources.

TDS, usually measured in parts per million (ppm) or milligrams per liter (mg/L), is a common indicator of water quality.

What factors affect the TDS?

There are many factors that affect the TDS, such as:

Geographical Environment: The content of TDS in groundwater and surface water varies from region to region. For example, certain areas may be rich in minerals due to geographical reasons, resulting in higher TDS values.

Human Activities: Industrial wastewater, the use of fertilizers and pesticides in agriculture, and domestic sewage all increase the amount of dissolved solids in the water, thus raising the TDS value. 

Climatic Conditions: Climatic factors such as rainfall, temerapture and evaporation can affect the concentration of TDS in water bodies. In arid areas, TDS values in water bodies may be higher due to high evaporation.

Water treatment process: Different water treatment processes have different effects on TDS values. For example, reverse osmosis technology can effectively reduce the TDS value of water, while simple filtration and disinfection processes have less impact on the TDS value.

Is TDS Good or Bad?

The effects of TDS depend on its composition and concentration. Not all TDS is harmful; in fact, some dissolved minerals are essential to health. However, excessive or inappropriate levels can cause problems:

• TDS < 300 mg/L: Generally considered to be good quality drinking water with good taste and suitability for consumption.
• 300 mg/L < TDS < 600 mg/L: is a medium TDS value and may require filtration or softening treatment to improve taste and suitability.
• TDS > 600 mg/L: Water with high TDS value may have poor taste and requires deep treatment, such as reverse osmosis and distillation, to reduce the TDS value.

Why is TDS important?

TDS affects water in many ways, from the taste to the impact on equipment and health. Here are the reasons for the impact:

Taste and quality: Water with a low TDS value may taste bland, while water with a high TDS value may taste salty, bitter or metallic. Moderate TDS levels usually result in better tasting water.

Health Effects: The essential minerals in moderate TDS levels contribute to good health. High TDS may include harmful contaminants such as lead, arsenic or nitrates.

Equipment Life: High TDS water can cause appliances such as kettles, coffee makers and water heaters to scale. This can reduce their efficiency and longevity.

Plants and aquatic life: Excessive TDS can alter the chemical balance of water, which can affect the health of plants and aquatic ecosystems.

How to Reduce TDS in Water?

If your water has high TDS levels, filtration systems can help. Common methods include:

• Reverse Osmosis (RO): Removes most dissolved solids through a semipermeable membrane, ideal for drinking water.
• Distillation: Boils water and condenses the steam, leaving behind dissolved solids.
• Deionization (DI): Removes charged particles through ion exchange.

TDS value is one of the most important parameters for assessing water quality, which affects the taste of water, health risks, and industrial and agricultural applications. With proper water treatment technology, TDS value of water can be effectively reduced and water quality can be improved to meet the water needs of different sectors. Understanding and monitoring TDS values is important to ensure safe drinking water and improve quality of life.