Well it should be obvious that I don't know much about it so I am just making assumptions. I thought the Kalk would eventually be gone if I dumped in a 500g package of it. I have alot more research to do before I decide on which way to go, for now I drip my kalk and so far things are good, I guess I just wanted an easier (more stylish) way to do it.

As I mentioned, if the incoming water is injected into the reactor, near the bottom, with an elbow pointing to the kalk powder, it will stir it up some.

This is the basis of the Tunze dispensor, which uses no mech mixer. This method works, but only for smaller tanks. For a large load, then a large reactor is needed, to be able to add more kalk and mix it without the powder being pushed out. I believe mine is 3ft high and mixes with a powerhead.

After looking at plans/pictures etc on the internet it is obvious a Kalk Reactor is going to be much easier to build than a Ca Reactor..... I love this DIY stuff.