TDS & PPM
TDS (Total Dissolved Solids): Total Dissolved Solids
-
Definition: Refers to the total amount of all inorganic salts and organic substances dissolved in water. These substances come from the rocks, soil, pipes, and pollutants introduced by human activities that the water flows through.
-
Main Components: Includes minerals such as calcium, magnesium, sodium, potassium (usually harmless, even beneficial), as well as heavy metals (lead, arsenic, cadmium), nitrates, fluorides, pesticide residues, etc. (harmful).
PPM (Parts Per Million): Parts Per Million Concentration
-
Definition: It is a unit of concentration, meaning “one part per million.” 1 ppm means that for every million parts of solution, one part is solute.
-
Analogy: Just like “kilograms” is a unit of weight, “PPM” is the unit for TDS value.
-
Equivalence: 1 ppm ≈ 1 mg/L (milligrams per liter).
Conclusion: The “TDS value” we commonly refer to uses the unit PPM. When someone says “the TDS of this water is 50,” they are referring to “the total dissolved solids concentration of this water being 50 ppm.” The “IN ppm” and “OUT ppm” displayed on your product's screen refer to the TDS concentration of the incoming (source) and outgoing (purified) water.
What Do These Parameters Mean for Water Purifiers?
For water purifiers, especially reverse osmosis (RO) purifiers, the TDS value is an extremely important performance indicator.
Core Function Verification: The core function of the RO membrane is to remove most of the dissolved solids in the water. A significant change in the TDS values of the incoming and outgoing water is the most direct proof that the RO membrane is working effectively.
-
Example for Your Product: The manual mentions it can process water with a TDS of <1500 ppm, producing water with a TDS of <18 ppm. This means the desalination rate is (1500-18)/1500 = 98.8%, which perfectly proves the superior performance of its RO membrane.
Filter Life Monitoring:
-
"Barometer" for RO Membrane Performance Degradation: Over time, the RO membrane will gradually be clogged, worn down, or chemically degraded, reducing its desalination capability. Users will notice the TDS value of the purified water (OUT ppm) gradually increasing.
-
Basis for Smart Reminders: The “Filter ⚠️” replacement reminder on your product's screen is based on the change in desalination rate. The TDS sensor provides the key data for this feature.
Incoming Water Quality Assessment:
-
The “IN ppm” value allows users to have a preliminary, quantified understanding of their source water quality. If the TDS value is too high (e.g., >500 ppm), it could indicate high water hardness (more scale) or heavy pollution, highlighting the need to install a water purifier.
What Valuable Information Can Users Obtain from These Values?
Water purifiers equipped with real-time TDS display functions give users unprecedented insight and control.
-
TDS Value ≠ Water Safety: TDS pens/sensors cannot detect specific pollutants (e.g., bacteria, viruses, lead, pesticides). They only measure the total amount of conductive ions. An RO purifier that reduces the TDS value usually removes most harmful ions, but overall safety should still be ensured through authoritative certifications like NSF. It is not accurate to simply say “water with TDS = 0 is the best.” Mineral water with higher TDS may still be beneficial to health.
-
Best Indicator for RO Purifiers: For RO water purifiers, the “low and stable OUT ppm value” and “high desalination rate” are the core performance indicators.
Related Products
Latest Articles
2025-10-26 09:35:33 -0500
Rare Earth Thick Film Heating Technology
"are Earth Thick Film Heating Technology is the most advanced, efficient, and user-friendly technology in the instant heating field today.
"Water-electric separation, absolute safety": The water flows inside the pipe, while the electric current runs outside, physically separated, providing the...
2025-09-15 09:30:00 -0500
Integrated Waterway
The integrated waterway is a revolutionary design. By using precision injection molding or metalworking processes, the originally separate pipes, connectors, water channels, and functional valves (such as the inlet valve, wastewater valve, and high-pressure switch interface) are highly integrated...
2024-12-26 09:41:00 -0600
304 Stainless Steel Shell
304 stainless steel contains 18% chromium and 8% nickel (hence the name "18/8 stainless steel"). Chromium forms a very thin and dense passivation layer on the surface, giving it excellent resistance to rust and corrosion in air or water. It is also resistant to common cleaning agents, ensuring lo...
2024-11-20 09:24:00 -0600
RO Reverse Osmosis Membrane
Reverse osmosis is the process of counteracting natural osmosis. By applying an external force greater than osmotic pressure (typically through a pump), water molecules are forced to pass through the membrane in the opposite direction. Soluble salts, metals, viruses, and other impurities are bloc...
2024-10-31 09:15:00 -0500
Composite Filter
The composite filter integrates various filtering materials and processes into a single filter to achieve multiple filtration effects. Its core function can be summarized as pre-filtration and taste pre-treatment.
2024-09-27 02:35:00 -0500
NSF Certification
NSF (National Sanitation Foundation) is an independent non-profit organization dedicated to setting standards, testing products, and certifying in the fields of public health, safety, and environmental protection.
2024-09-18 04:06:00 -0500
SGS
SGS is the world’s leading inspection, verification, testing, and certification company, widely known as the international “benchmark for quality and integrity.” Its core values lie in independence, impartiality, and professionalism.
Back to Top
support@purifighter.com
+1 (840) 244-5726
