Municipal water company CO2 use

VaughnH

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Jan 24, 2005
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How common is the practice by water companies of injecting CO2 in tap water to control the pH? Direct CO2 (Carbon Dioxide) Injection Water Treatment Systems I didn't know this was done at all, until a post on TPT about a water problem related to CO2 being injected to reduce the pH of water that was also treated with sodium carbonate. If this is common practice, doing water changes for a non-CO2 tank really creates an ideal breeding ground for algae.
 

Tom Barr

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Jan 23, 2005
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It's used to lower pH after partial lime softening.

They raise the pH to 10.1 to preciptate out the CaCO3...........then it's "soft", pH is still high.........and they add CO2 to lowerit back before heading off to the next treatment process, hopefull about 7.5-8 pH.

It's common where hard water is softned at the treatment plant.

Tap is loaded with CO2 anyway due to pressure(higher pressure holds more gas in solution), colder temps (same thing), ground water sources or deep intakes etc.

In general, tap has more CO2 than most other sources of water.
Springs are loaded with CO2 as well, think carbonated spring water............

Regards,
Tom Barr

Regards,
Tom Barr