Do you want to passive drip or use a dosing pump?
I always used passive drip because I'm a member of the KISS (keep it simple stupid) army...
I took a 200 gallon RC salt bucket and drilled and tapped a hole in the bottom of the bucket about and inch off the bottom. I went to the hardware store and picked up some of the water line and pressure clamps they use for refrigerators. I super glued and then siliconed both sides.
This setup gave me 5 to 6 gallons of kalk mix at a go. I only mixed 1 tbsp per gallon so there isnt a concern about the sludge. Not to mention, with only 5 gallons of the stuff, even if the whole thing dumped into my 150, it wouldn't destroy my tank. This is the advantage of this system over a Nilsen reactors.