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Tap water soft, but high pH?!

Posted by howelbama none (My Page) on
Thu, Sep 8, 11 at 18:48

My tap water usually runs about 8.2 to 8.4, so I have always assumed it was very hard. However, I just did a general hardness and carbonate hardness test and they both indicated 50 ppm or less, which is really soft. In fact it is almost as soft as ro which comes in at a little under 20 ppm.

I think going forward I am going to start using my tap since it so soft and just pH adjust it. Ro is much more expensive and wastefull.

Any ideas what would cause my tap to be soft but still have such an alkaline pH?

Follow-Up Postings:

RE: Tap water soft, but high pH?!

Because the two are not the same.
Hard water has high concentrations of Ca2+ and Mg2+ ions
You can see this when water evaporates as in boiling leaving a white chalky ring around the kettle.

In chemistry, pH is a measure of the acidity or basicity of an aqueous solution.[1] Pure water is said to be neutral, with a pH close to 7.0 at 25 �C (77 �F). Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline.
The pH of table vinegar ranges from 2.4 to 3.4[1] (higher if diluted).

RE: Tap water soft, but high pH?!

I pulled my water suppliers reports, and the reports are actually quite nice. No fluoride at all, not that tat is really a concern for my plants, I just don't want to consume it if I can avoid doing so... Also they only use chlorine to dissinfect, no chloramines, and chlorine is easy to gas off. Looks like I was wasting my money and water with my ro system...

I'm going to allow some water to gas off overnight and see how much lower the pH comes out just out of curiosity as I have only tested it immediately after taking the sample which is probably not that accurate.

I'm guessing they add sodium bicarbonate or something else to buffer and raise the pH to avoid corrosion int the mains, but I did not see anything in their quality reports regarding that.

RE: Tap water soft, but high pH?!

Mine is in the range of 8.5 also.

I use vinegar which lowers the pH of the water solution and gets me by very well all winter.

On the plants I water with tap water,they get by, but look less than perfect by the time spring comes.

I also save rain water in barrels all winter in which I water my most special plants with and they thrive. I use to run out and buy water, but no need to any more.


RE: Tap water soft, but high pH?!

Yep, ya can't beat rain water with it's low pH and no chemicals. I filter mine, and store it in plastic 55g barrels, which last me all winter long.

Howelbama, I have to ask, why would you avoid consuming fluoride?


RE: Tap water soft, but high pH?!

Joe, google it. Its just no good, calcifies glands etc... I use Tom's natural toothpaste and avoid water that is treated with it if possible.

RE: Tap water soft, but high pH?!

Although I don't agree 100%, I respect your position. I don't want to hijack this thread and start up a fluoride debate though, so I'll keep it somewhat brief. Fluoride comes in many forms, of which some have a higher toxicity than others. Different water utilities use different kinds, but none are scientifically proven to be toxic at the levels that are in drinking water. Also, fluoride occurs naturally in many areas in the groundwater, lakes, and rivers. This leads to many sources, municipal and non, containing fluoride, some in excess of what is added intentionally.

Anyway, fluoride is very important to your teeth, helping to fight cavities by protecting your tooth enamel. But, at the same time, what gives the government the right to put it on our water supplies, without our consent? I believe in small government that stays the heck out of our private lives, so I don't believe they should be putting things in our water that THEY think is good for us. Let us decide, and if we want fluoride to help our teeth, we'll provide it ourselves.

So, long story short, I think fluoride is beneficial, but I think we should have the right to decide ourselves, and the government shouldn't force it on us. Its no different than this garbage with the lefties forcing us to use compact fluorescent lightbulbs. Just leave us alone and let us live our lives in this "free" country.


RE: Tap water soft, but high pH?!

Joe, I do use it ocassionally topically..via toothpaste for prevention of tooth decay. But there is no proven benefit of ingesting it, in fact there is only evidence of harm when it is ingested, even at the low concentrations found in drinking water.

I agree with you that it should be our choice to consume something or not.

Check out the link below if you feel like it...lots of interesting info on the topic, and no worries about high-jacking the thread.

Here is a link that might be useful: Fluoride info

RE: Tap water soft, but high pH?!

  • Posted by tapla z5b-6a mid-MI (My Page) on
    Fri, Sep 9, 11 at 22:28

The pH of freshly drawn tap water will rise if you leave it set overnight because of something called pH rebound. The pH of tap water is partially controlled (kept lower) by the CO2 dissolved in water, some of which forms carbonic acid and lowers pH. In water left to rest, excess CO2 gasses out and you'll see pH rise. That's why I usually suggest that those adjusting the pH of their irrigation water or fertigation solution adjust to 5.0 - to allow for rebound. If you want DD (deeper detail), ;-) search "pH rebound" and/or "Henry's law".


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