New acid neutralizer, high pH

[DKH53]

I see another thread by Althea Later with similar questions but my equipment is slightly different so thought I would start a new thread.

Well water tested for the first time found pH 5.5. Hardness 24 mg/L. Nothing else exciting in the test result.

Purchased and installed a Fleck 5600 SXT, a pressure tank, D tube, gravel, calcite, and Flomag. Plumbed in the system, put D tube in tank, add 12 lbs gravel, add calcite/Flomag mix. Based on what I was reading I decided to go with a small amount of Flomag so the initial fill was 100 lbs calcite with about 7 or 8 lbs of Flomag mixed in (using 5 gallon bucket I poured in 12.5 lbs calcite then 1 lbs Flomag, stir to mix, then pour in the tank, repeat). My thinking was my pH would be better than 5.5 and over time I could adjust the Flomag to zero in on a pH of 7.

Ran about 100 gallons through the new system and tested the pH with a $20 pH meter from Amazon. I measure pH at 6.6 so I'm very happy. Next day I measure pH at 8.5 (first thing in the morning, no water has been used in hours). Not happy. I check the pH meter against calibration solutions it came with and with distilled vinegar and bottled water. I am convinced the pH meter works but is only accurate to maybe 0.5 pH. Day 2 with the new system I run the faucet for about a minute and check pH, now 9.0. Day 3 I get 9.5. Very unhappy, I am further from pH 7 than when I started worrying and buying the acid neutralizer.

I did a backflush and Rapid Rinse. after that I measure pH of 6.8. I'm happy.

Next day is today and woke up, ran the kitchen faucet a few minutes and tested pH. I get 9.7. Then I run the faucet for 10 minutes while flushing toilets and running the shower to get a lot of flow and test again, now I measure 10.1 in the kitchen. I am rapidly approaching the pH of ammonia. I leave everything running for another 10 minutes and now in the kitchen and 2 bathroom faucets I measure pH around 7.2.

I rechecked the meter today after these readings, it is to my best guess accurate to within pH of +/- 0.5.

My Qs:
1) Why is pH so high? Calcite should not dissolve once pH gets close to 7 so is self limiting from my limited understanding.

2) I want to take a water sample to a lab to confirm pH and to find out how much I have increased the hardness. My pH meter varied today from 10.1 to 7.0 depending on which faucet and how long the water had been running. So which sample do I take to the lab?? My kitchen faucet at 10.1 pH or my kitchen faucet at 7.0??

3) Is Flomag the same thing as Corosex? Maybe I overshot the pH because the Flomag gives up Hydrogen faster/easier than calcite or corosex?

 

[ditttohead]

I assume you read about calcite and flomag online... what you read and the real word are going to be totally different. Calcite and magnesium do not adjust the water perfectly and yes they can and will over correct. When water sits in the calcium carbonate or magnesium oxide, the water will continue to dissolve the minerals into the water. The amount of "correction" will vary significantly based on numerous factors... co2 levels, flow rate, temperature etc. In your case a better solution might have been a simple injection system. These will tend to keep the water more consistent without adding hardness.

 

[Sponsor]

 

[DKH53]

I am confused...a "simple injection system" you refer to is a soda ash injection system?

 

[Reach4]

I am confused...a "simple injection system" you refer to is a soda ash injection system?

That would be one choice, but there can be alternatives, such as potash, and there can be a combo in some cases, I expect.

 

[ditttohead]

Soda Ash, Pot Ash, Sodium Hydroxide... Soda Ash is the safest since a problem with the system (runaway pump) is unlikely to cause any serious injury. Done correctly with the right high end equipment it would typically be a little more cost than a calcite system but it will be far more consistent.

 

[Reach4]

Soda Ash is the safest since a problem with the system (runaway pump) is unlikely to cause any serious injury.

Also soda ash going to be cheaper than potash, but some willingly pay the premium, just as some use KCl salt in softeners, at maybe 5x the salt cost. At least the potash is not going to have the other problems of KCl in softeners.

 

[Paul J Burkhardt]

I believe the high pH is due to the Flomag. I use straight calcite in a standard 1054 tank to raise pH from about 6.0 to averaging around 7.0 as long as the calcite level is enough for the water to have enough contact time (exposure to the calcite). Calcite can continue to raise pH above 7.0, but usually not much higher than about 7.5.

Flomag is a very powerful acid reducer that I only use in very light mixes with calcite, about 5% Flomag to 95% calcite. Not only because it causes fluctuations in pH, but it can also clump together inside of the tank and create channeling which means that the water is only traveling through the Flomag through certain areas.

I would cut way back on the Flomag and see how your pH is then. I prefer going with a larger tank with straight calcite rather than using strong acid reducers like Flomag/Corosex.

 

[Reach4]

For those following along, Flomag and Corosex are brands of magnesium oxide media.