How to check for water hardness

I had to do this not too long ago:

How to Test for Hard Water
You can do a fairly reliable unscientific test to see if you have a problematic level of hard water in your home by doing the following test:

• Open your tap water faucet and fill up a bottle having a cap with about a half-cup of water;
• Add 10 drops of dish washing detergent;
• Shake well;
• If the soapy solution foams up quickly you are good and the water is not hard;
• If it does not foal up but instead creates a milk-curd-like or soapy film on the water then the water is likely hard.
• If you have hard water scale build-up on your shower door or white scale on your faucet aerator, this is also another indicator your water is too hard.

You can also send a water sample out for testing to a certified water testing laboratory. Hard water is anything above 1 grain of hardness per gallon[/link]. (A grain of hardness is an amount of calcium and magnesium equal in weight to a kernel of wheat).

• Less than 1.0 = Soft
• 1.0 - 3.5 = Slightly Hard
• 3.5 - 7.0 = Moderately Hard
• 7.0 - 10.5 = Hard
• Over 10.5 = Very Hard

You are very welcome !

water hardness is one of the most improtant parameters should be known when testing the water for any application or use or even purpose.

hardness relates to the calcium carbonate ( CaCO3), this chemical compound is insoluble in the water or has a very low solubility , which normally forms a precipitate  appreats as a white film or scale on the boiler wallas or the kettles

the hardness can't be tested by us , but some methods can be used to indicate it in the water , one of them is to boild or to dry a cup of water and then you can observe the white ppt or the film on the wall of the vessel

the thing people know that hard water doest make foams  but when we boil the heat the water , the solubility of the calcium carbonate becomes more and the water then become roughly soft , but at the normal conditions , still hard

indicating the hardness in the water can be expressed in ppm or mg/l

as we know the molecular wt of the calcium carbonate = 100 gm/mole

and the eq wt of the caco3= 100/2 = 50

and we express it in terms of ppm (Ca+2) Ions in the water

mw of ca = 40 gm/mole

so the caco3 hardness = (ca+2) *2.5 ppm caco3

another term we have to understand , its called the total hardness

total hardness refers to the caclium and magnisium hardness

so we apply the same conditions for both to find the total hardness , this is our concern when we test the hardness in the water

so to find this value , the only thing to do is to take a sample and test it in a lab

or use a high tech lab instrument like HACH equipemnts which give you a high accurate result for a such parameter

in the water treatment field, the water softener is the only one used to remove the hardness from the water and give a  soft water

the ion exchange is the process where the caco2 is replaced by Na ions existing on the surface of the resin beads