Lower pH after calcite neurtralizer bed

[RalphVa]

Anyone else run into this?

Just recommisssioned our calcite bed. Had it bypassed since June, 2021 because of water hammer when backwashing. Been monitoring pH. Was always above 7 until about 3 or 4 weeks ago and had dropped to 6.9, 6.7, etc.

Broke one of the valve handles when I tried to open up the valves on the old Amtrol unit. Called Amtrol, and they said haven't made in over 15 years. Contact Watersoft. Did, and they sent me to a web site to order a new valve. Did.

Called an outfit different from the plumber who'd put the unit it because we hated dealing with him. This new local outfit came out and replaced the valve. Put it in a backwash to flush the tank/bed.

Well, I measured the pH before and after yesterday: 6.6 before and 6.3 after.

What is going on? Found one online reference where a guy measured the same thing one time on his calcite bed.

Calcite is just calcium carbonate, more or less pieces of carbonate rock.

Before the bed was bypassed the well water pH was runnning above 8. After the bed, it was measuring just below 8. So, this was happening then, too, except one time when it was 7.5. Came out of the bed @ 8.

 

[2LaneCruzer]

Here's something I found. According to these guys, the pH should go up slightly, not down.

Does Calcium Carbonate (CaCO3) effect water pH level?

Answer (1 of 6): CaCO3 has very low solubility in water. It is a salt of a fairly strong base (calcium hydroxide ) and a weak acid (carbonic acid). In aqueous solution such salts undergo hydrolysis to give free OH- ions, and so the solution will be basic in character. CO3(2-) + H2O = HCO3(-) + ...

www.quora.com

 

[RalphVa]

Reading 6.6 before the bed and 6.3 after it. Was doing similar before I bypassed it June, 2021 but much higher pH values. The left hand column is before the bed off the pressure tank. The right hand column is after the bed.

Yeah, the purpose of the bed is to raise the pH, to protect copper piping.

 

[Larry Caldwell]

I wish I had known about this years ago. I had to re-plumb my house last year because the old copper had gotten paper thin and was springing leaks. Yeah, calcite is slightly basic, and the pH should run about 8. I have no idea how you are getting a pH below 7. Maybe the flow rate is too high?

 

[RalphVa]

I'm wondering if the bed is depleted. I measured at the tap again today: 6.6. This would be after the bed.

Even more puzzling is depleted or not why it is lower coming out of the bed.

 

[2LaneCruzer]

It's possible that what you bought, wasn't what you got. You might check your source. I know when I worked at the lab, they bought a batch of calcite to treat some effluent water, so they tested it when it didn't function properly. I turned out to be dolomite, a Magnesium salt.

 

[RalphVa]

The bed was recharged Sep 2020. He was due to come back this September, but I've had the bed bypassed since June, 2021. Just put back in service. Figured it should still be good. Water pH ever since it was recharged has been well above 7 until recently.

Have called the outfit that replaced the valve on it. They're coming this Thursday to recharge it.