[untamed]

Originally Posted by xenon

Kalk is an excellent way to maintain calcium and alkalinity in a balanced way. The major advantage is that it also increases PH.

Wit that said, there is only so much kalk you can dose when you saturate your top-off water with kalk. If you have a heavily stocked tank (lots of corals) it won't be enough.

You can alternatively blow a fan across the water surface of your tank to evaporate more water so that you can top-off even more but it may still not be enough evaporation to keep up with demand.

I know what some with heavily stocked tanks top-off with kalk and also use a dosing pump. The reason for this is the increase in PH from kalk.

I completely agree. Once CA/Alk demand gets high enough, it becomes really difficult to keep up with Kalk alone due to the limit of how much fresh water you can add along with the Kalk. There are some methods to super-saturate the Kalk...but things get increasingly tricky.

I run my Kalk reactor to the max overnight when pH is lowest and also run a CA reactor.