I used to use kalk for makeup water, about 1 gal per day in my 75G. I also had so supplement this with B-ionic. When the B-ionic additions got up to 90ml per day, i broke down and built a calcium reactor. Now my calcium and alk are easily maintained. I'll add a nilsen reactor when I upgrade to a 300. That way I can also enjoy the benefit that kalk helps drive phospates from your sysmem. I have noticed slight increase in nuisance algeas since I stopped using kalk. I have also notice significant increase in SPS growth since I started using the calcium reactor.
