Don't worry, mg/L is the same as PPM. http://www.milwaukeeinstruments.com/...0and%20ppm.pdf
I'm getting conflicting advice on this. People generalise Perth has hard water but my coffee guru says it's not quite so. So I called Water Corp who said the source of my water is Mt Elisa (aka Kings Park) is actually quite soft at 66gm/L. If however you lived up north in Yanchep or Two Rocks it's over 220gm/L!
So does anyone know if gm/L is the same as ppm as the Water Corp guy didn't know?
I'm currently looking at water filtration so this will influence my needs.
It's not actually the same. Its just close enough for most practical purposes when the density is close to 1000 g / L (i.e. 1,000,000 mg / L).
What's the difference between hardness and TDS? I always thought TDS is what is used to gauge water hardness?
TDS is the total mass concentration of solids dissolved in the water. Hardness is a measure of only a portion of the dissolved salts (i.e. not the same). Dissolve a few tablespoons of table salt or cane sugar into a litre of water and you increase the TDS, but not the hardness.
The Australian Drinking Water Guidelines (pg 22) describe hardness as followshttp://www.nhmrc.gov.au/guidelines-publications/eh52GENERAL DESCRIPTION
Hard water requires more soap than soft water to obtain a lather. It can also cause scale to form on hot
water pipes and fittings. Hardness is caused primarily by the presence of calcium and magnesium ions,
although other cations such as strontium, iron, manganese and barium can also contribute.
Total hardness is the sum of the concentrations of calcium and magnesium ions expressed as a calcium
carbonate equivalent. Hardness may also be classified as carbonate (temporary) or noncarbonate
(permanent) hardness. Carbonate hardness is the total alkalinity expressed as calcium carbonate, where
alkalinity is the sum of the carbonate, bicarbonate and hydroxide content. Noncarbonate hardness is the
difference between the total and carbonate hardness.
Last edited by MrJack; 20th October 2015 at 10:14 PM.
Thanks for the info. I have used a little gadget that measures TDS and was measuring around 450 out of the tap.