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Water Treatment Issues:

Acid Water

Algae, cyanotoxins

Alkalinity

Alum (Aluminum Sulfate)

Aluminum

Ammonia

Arsenic

Asbestos

Bacteria

Barium

Benzene

Bicarbonate Alkalinity

Boron (Borate, Boric Acid)

Brackish Water

Bromine

Bromate

Cadmium

Calcium

Carbon Dioxide

Carbon Tetrachloride

Chloramines

Chloride

Chlorine

Chromium

Color

Copper

Corrosion

Cryptosporidium

Cyanide

Dichloroethylene

Endocrine Disruptors

Fluoride

Giardia Lambia

Hardness

Heterotrophic Bacteria (HPC)

Hydrogen Sulfide

Iodine

Iron

Iron Bacteria

Lead

Magnesium

Manganese

Mercury

Methane

MTBE

Napthalene

Nickel

Nitrates and Nitrites

NMDA (N-Nitrosodimethylanime)

Norovirus

Odor

Organics

Perchloroethylene (PCE)

Perchlorate

Pesticides

pH

Pharmaceuticals

Radon

Radium

Selenium

Silica

Silver

Strontium

Sulfate

TDS (Total Dissolved Solids)

Trichlorethylene (TCE)

Tritium

Uranium

Vanadium

Vinyl Chloride

VOC


Total Dissolved Solids (TDS)

TDS, total dissolved solids, is defined by a leading maker of test equipment as follows:

Total Dissolved Solids (TDS) are the total amount of mobile charged ions, including minerals, salts or metals dissolved in a given volume of water, expressed in units of mg per unit volume of water (mg/L), also referred to as parts per million (ppm). TDS is directly related to the purity of water and the quality of water purification systems and affects everything that consumes, lives in, or uses water, whether organic or inorganic, whether for better or for worse.

 

  • The U.S. EPA sets the maximum contaminant level for TDS at 500 ppm.
  • The World Health Organization (WHO) sets the maximum contaminant level for TDS at 1000 ppm.

 In reality, many city water departments are in violation of the suggested TDS level because there is very little city water departments can do to reduce TDS.

For practical purposes, small handhell TDS meters to an excellent job of reading TDS. The most common use for TDS meters is in the verification of the performance of Reverse Osmosis units. Typically , Reverse Osmosis rejects 90% plus of the total dissolved solids, so with a tap water TDS reading of 200 ppm, a reverse osmosis reading of 20 or less would be expected.

Most fresh water that is consumed by humans falls in the <1000 ppm category. Here's how the Water Quality Association ranks water according to TDS:

Fresh: <1,000 ppm TDS
Brackish: 1,000-5,000 ppm TDS
Highly Brackish: 5,000-15,000 ppm TDS
Saline: 15,000-30,000 ppm TDS
Sea Water: 30,000-40,000 ppm TDS
Brine: 40,000-300,000+ ppmTDS