Low ph of new kalk solution in stirrer

[mrdanielface]

I just cleaned out and replaced my kalk solution in my avast k1. On the previous fill my ph started at 12.4 then went down to 11.5. I cleaned it out because when I first set it up the plug for the ph probe fell thru the hole and went into the bottom of the stirrer. Doh. Anyways, on the fresh new solution, the ph started at 11.7 and 3 days later it has decreased to 9.28. What is happening here?

 

[HuduVudu]

Check the probe. Calibrate it, and verify against a liquid pH test.

Are you dosing more or the same?

Also I would check the pH of the incoming RO.

 

[mrdanielface]

ill try that out. thanks. im dosing the same. also i put the same amount of kalk into the stirrer.

 

[HuduVudu]

ill try that out. thanks. im dosing the same. also i put the same amount of kalk into the stirrer.

Make sure that you keep the kalk in a cool dry place. Humidity can cause the kalk to "go bad".

 

[Randy Holmes-Farley Verified Community Expert]

Check the probe in truly saturated kalkwasser (say, 2 tablespoons solids in a cup of Ro/DI).

That will serve as a calibration of the probe and tell you if the reactor solution is sub par or not.

A difference of 0.3 pH units is a factor of 2 in potency.