[untamed]

If you are thinking about adding vinegar to the Kalk in order to get MORE out of Kalk, I suggest it is time to be looking at a Ca Reactor. If you are already max'd out on saturated Kalk, it won't be too long before you are max'd out on super-saturated-vinegar Kalk too.

IMO, Kalk reactors/stirrers are most useful in that they allow you to pump FW in, and get Kalk out. In this way, your osmolator pump doesn't have to pump Kalk so it doesn't get that wear you were concerned about. Any Kalk container will do the same thing, provided that you can get a pressure seal. I don't think the actual mixing aspect of the Kalk reactors is as important.

Remember that evaporation changes day to day. If Kalk is your only Ca/Alk replacement and it goes in based on evaporation, then the amount of kalk you add changes every day...then you will have more trouble keeping Ca/Alk really steady.