Aqua Pure Filters

Total Dissolved Solids

Source of Total Dissolved Solids

Total Dissolved Solids (TDS) consist mainly of carbonates, bicarbonates, chlorides, sulfates, phosphates, nitrates, calcium, magnesium, sodium, potassium, iron, manganese, and a few others. They do not include gases, colloids, or sediment. The TDS can be estimated by measuring the specific conductance of the water. Dissolved solids in natural waters range from less than 10 mg/i for rain to more than 100,000 mg/I for brines. Since TDS is the sum of all materials dissolved in the water, it has many different mineral sources. The chart below indicates the TDS from various sources.

Total Disolved Solid (mg/l)
Distilled Water (0)
Two-column Deionizer Water (8)
Rain and Snow (10)
Lake Michigan (170)
Average rivers in the U.S. (210)
Missouri River (360)
Pecos River (2,600)
Oceans (35,000)
Brine Well (125,000)
Dead Sea (250,000)

High levels of total dissolved solids can adversely industrial applications requiring the use of water such as cooling tower operations; boiler feed water, food and beverage industries, and electronics manufacturers. High levels of chloride and sulfate will accelerate corrosion of metals. The US EPA has a suggested level of 500 mg/i listed in the Secondary Drinking Water Standards.

Treatment of Total Dissolved Solids

TDS reduction is accomplished by reducing the total amount in the water. This is done during the process of deionization or with reverse osmosis. Electrodiaiysis will also reduce the TDS.