Composition of seawater

Major ion composition of seawater (mg/L)

	Typical Seawater	Eastern Mediterranean	Arabian Gulf at Kuwait	Red Sea at Jeddah
Chloride (Cl^-)	18.980	21.200	23.000	22.219
Sodium (Na⁺)	10.556	11.800	15.850	14.255
Sulfate (SO₄^2-)	2.649	2.950	3.200	3.078
Magnesium (Mg²⁺)	1.262	1.403	1.765	742
Calcium (Ca²⁺)	400	423	500	225
Potassium (K⁺)	380	463	460	210
Bicarbonate(HCO₃^-)	140	-	142	146
Strontium (Sr²⁺)	13	-	-	-
Bromide (Br^-)	65	155	80	72
Borate (BO₃^3-)	26	72	-	-
Fluoride (F^-)	1	-	-	-
Silicate (SiO₃^2-)	1	-	1,5	-
Iodide (I^-)	<1	2	-	-
Others	-	-	-	-
Total dissolved solids (TDS)	34.483	38.600	45.000	41.000

Note: The dot (.) separates thousands
The comma (,) separates decimals

Source: Magazine - Water Condition & purification, Januray 2005

Reverse Osmosis Systems
Softener Unit FAQ

Currently the world uses 11.000 desalination plants to produce daily 20 million cubic meters per day. They mostly use seawater with an average TDS of 40.000 ppm and brackish water with an average TDS of 10.000 ppm and can be found in each continent

West Asia & Middle east	60%
North America	11%
North Africa	7%
Europe	7%
South and Central America	4
Other	11%