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Curated with aloha by
Ted Mooney, P.E. RET
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TDS is lower then Total hardness
Is it possible, the total Hardness is higher then Total Dissolve Solids (TDS) of the same water.
Anwar Hossain- Dhaka, Bangladesh
February 2, 2011
Hi, Anwar. If the two parameters use the same units I can't see how that is possible. Please put your question into context. If this a question on a homework assignment? Is a lab reporting such results? Thanks.
Regards,
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Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
February 2, 2011
It is not possible. However, if you are measuring the TDS with a TDS meter, the reading is probably incorrect because it actually measures conductivity, not TDS. The most accurate way to measure TDS is to evaporate a filtered sample to dryness and to weigh the residue.
Lyle Kirmanconsultant - Cleveland Heights, Ohio
February 3, 2011
If the hardness is being reported in mg/l CaCO3, but is present as magnesium, the results you describe are possible.
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Dave Wichern
Consultant - The Bronx, New York
February 13, 2011
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