hopefully somebody else will chime. Your calcium reactor can only MAINTAIN your calcium level that you set it at. You have to use supplement to raise the calcium level and then the reactor will try to keep it at that level. You can only teak PH and alk from the reactor but not alk and calcium.
here is how i adjusted my GEO 612..
increase BPM= high effleunt alk and low PH
increase effleunt drip= high PH and low alk.

i raised kalkwasser dose to get hiher alk, but that will raise PH too, so raise it slowly.
..hope that help.