The best way to add calcium

[Aquattro]

I have yet to see anyone successfully raise calcium and/or alk by dosing kalk. Based on opinions of chemists (Randy Holmes-Farley, Craig Bingman) rather than sales monkeys, I would say that info is not correct. I have also tried to raise levels with kalk when I first started in the hobby, and I was not successful. As an aside, I am fairly certain I have seen this same info on Kent's website at some time. I'll take a look.