Water Quality/TDS


Hi Steve

I have  bottled water its pH is between 6.5 and 7.0 (measured with pH paper 1-14). TDS is 62ppm (measured with TDS EZ meter). Total hardness is 7 gpg (measured with Sesafe total hardness strip).

When I boiled down above water to half volume ( about 350 cc to 150cc) TDS became 156ppm. There is no precipitate in the bottom of beaker. What do you think what solid compound are in this water.

And I have a tube well. It has 485 TDS. I boiled down some 300cc of this well water to 100cc. TDS became 1400ppm and some precipitate are seen in this water. What do you think what compound are in this water.

Thanks in advance
Best regards
Hlaing Oo
95A Woodland Drive
Uncasville CT 06382

Hello Hiaing,
I am not sure what you mean by a "tube" well?? It would be easier, in my opinion, to have an analysis done on the water to be sure. Depending on where you live, you can probably get the county to do a complete water analysis for you.  Or you can get a good test kit online for a very reasonable price.

If you had measured alkalinity before boiling we might be able to figure out how much of the TDS was due to carbonates because some CO2 will boil off.  Also, the lack of ppt. in the test (350-150) doesn't mean anything because some ppts require total boil down.

Let me know if you have any questions.


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Water Quality

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Steve Young


I will answer questions on residential water treatment, i.e. use of softeners, filters, reverse osmosis systems, disinfection, iron and/or sediment removal and other issues facing the homeowner. I have worked extensively with well water systems.


I have worked in the water treatment area for many years as a consultant and as a professional environmental engineer in the private industry sector. I have designed reverse osmosis, deionization, and water softening systems. I have also done work in water quality and stream and river remediation as it relates to the Clean Water Act.

I am currently serving as an Expert for Home Improvement, Travel (New Mexico) and Travel (North Carolina);

BS Environmental Eng.

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