I have a PH probe in the reactor, so when the ph drops below 12.3, I add more Kalk. I think my main problem was the dosing pump I was using was small, so I don't think I was adding that much. Certainly dosed more Kalk solution than I am CalRX effluent.I would suggest that the minimal effect is probably due to low saturation in your kalk reactor. Kalk is notoriously hard to keep saturated (with reactors). Until I started measuring the saturation with an EC meter, I always over estimated the saturation of the effluent.
I have a thread on here about the challenges of getting kalk to dissolved in reactors.
Dennis