A Digital TDS meter is a hand-held instrument that used to indicate the Total Dissolved Solids in a water solution. It works based on the electrical conductivity of the water. When the dissolved ions increase then the conductivity of a solution increases. Normally, the TDS value represents as ppm. A TDS meter does not measure all kinds of contaminants such as heavy metals, pesticides, pharmaceuticals, or hexavalent chromium. Because these compounds are not ionic compounds.
What is TDS
TDS stands for Total Dissolved Solids and represents the total amount of the soluble substances that are dissolved in the water. It can be organic or inorganic matter. Ingredients usually dissolved in water are calcium, manganese, sodium, potassium, copper, iron, other trace metals, chlorides, sulfates, dissolved dust, fertilizers, and all chemical treatment. These materials are entered into the water in different ways. These can be human activities or natural sources. The groundwater is normally hard water. On the other hand, although the rainwater is soft water, it travels through the soil and rocks, so it dissolves small amounts of minerals like calcium and magnesium salts and retains the solution. Moreover, we use fertilizer on the land, different chemicals in many industries. These chemicals also mix with the water in different ways. The lower TDS level indicates the water is soft whereas the higher TDS level indicates hard water.
Why should you measure total dissolved solids?
TDS is a parameter of water quality. A high concentration of TDS can produce hard water and it may cause some problems. Usually, a high TDS level is not a health hazard, but it is an indicator that the water may have present harmful contaminants, such as lead, copper, manganese, arsenic, etc. Although A specific amount of magnesium and calcium, are beneficial to our health. Moreover, it may improve the taste of water. The pure water is absent of taste, odor, and color, but high TDS water could be bitter, salty, bad odor, and colored. According to EPA water standards Canadian guidelines, the maximum acceptable level of TDS for drinking water is 500 ppm. But the TDS level over 1000 ppm probably unfit for human consumption. Increased level of dissolved solids can also have some technical problems such as boiler maintenance, filter maintenance, Plumbing and appliances, pool maintenance, cooking, cleaning, stain household fixtures, etc.
Digital TDS meters have been made depending on the electrical conductivity of the sample water. The electrical conductivity of pure water is zero. The electrical conductivity increases with the increase of the amount of Dissolved ions. There are many TDS meters available in the market. Therefore, some factors such as the price of TDS meter, used technology, battery saving features need to be carefully considered when purchasing a TDS meter. Following are some good quality Digital TDS meters.
1. HM Digital TDS-3 Handheld Digital TDS Meter With Carrying Case
The HM Digital TDS-3 Handheld TDS Meter is Ideal for commercial use. It comes with a Carrying Case with Belt Clip and a user’s guide. It uses Advanced Microprocessor Technology, so you will get Highly Efficient and Accurate result. It can Saves Measurements for Convenient Reading and Recording. It has a Built-in Digital Thermometer that can Measure 0/80 Degrees Celsius. It contains two LR44 batteries and LCD Screen. The LR44 batteries are available in the local market and amazon, so you can buy them if necessary. The meter is Factory Calibrated with a 342 ppm NaCl solution. which is not included. You can buy this from HM Digital. The Measuring Range of this TDS is 0-9990. It is Better than HM Digital TDS-4.
Pros
- Includes a Carrying Case
- Easy to use
- It has a Built-in Digital Thermometer
- uses Advanced Microprocessor Technology
- It comes with a warranty.
- Quick results
Cons
- not included Calibrated solution
- Average quality
2. Water Quality Tester, Accurate and Reliable, HoneForest TDS Meter, EC Meter & Temperature Meter 3 in 1
The HoneForest TDS Meter is accurate and reliable and easy to use. It measures TDS, EC, and Temperature 3 in 1. It is ideal for drinking water, aquarium, hydroponics(test nutrients), Aquaculture, pool and spa, water treatment, and more. They offer 3 years warranty. It uses Advanced Microprocessor Technology. It has an auto-lock function to conserve battery. It comes with A colorful TDS chart on the back to explain ppm readings, a protective carrying case with belt clip, and a HoneForest Instruction. The Measuring Range of this Digital TDS meter; TDS: 0 – 9990 ppm, Conductivity: 0 – 9990 µs/cm, Degrees Celsius: 0.1 – 50.0°C. The meter is Factory Calibrated and they also said that no need for further calibration.
Pros
- Includes a Carrying Case
- Easy to use
- It has a Built-in Digital Thermometer to measure 0.1 – 50.0°C
- Low price
Cons
- not included Calibrated solution
- Average quality
3. HM Digital AP-1 AquaPro Water Quality Total Dissolved Solids Tester
HM Digital AP-1 is great for checking the drinking water quality, water filtration and purification, hydroponics, colloidal silver, aquariums, RO/DI systems, pools and spas, and more. It has an Automatic Temperature Compensation that can Measure 0/80 Degrees Celsius and an easy-to-read LCD screen. It contains one CR2032 3v battery. The meter is Factory Calibrated with a 342 ppm NaCl solution. The Measuring Range of this TDS is 0-5000 ppm. It is durable, consistent, and worthy of purchase. You must store the meter in the fridge after use it.
Pros
- Easy to use
- It has an Automatic Temperature Compensation (ATC)
- Water-resistant housing
- Auto-off function
- Data-hold function
Cons
- not included Calibrated solution
- slightly costly compared to the other products
4. KETOTEK Water Quality Test Meter, PH Meter TDS Meter 2 in 1 Kit
KETOTEK Digital TDS meter and has to function of Auto-off, it will automatically shut off with inactivity to save the battery’s life. It is easy to use, just need to press “ON/OFF” to open and use it, and just need to press “ON/OFF” to close it. It has an Automatic Temperature Compensation that can Measure 0/80 Degrees Celsius. It has a measurement range of 0-9990ppm and ±2% accuracy.
Conclusion
The Digital TDS meter cannot indicate the types of or the total amount of contamination. It will not tell us if the water is healthy or not. It can indicate to us the water may be suitable for drinking or it may be contaminated with harmful chemicals. Thus we can take our next steps.