I did Alkalinity and Calcium testing these couple of days. My KH is in normal range 7-8KH, but the Calcium level has been rather low 280-300ppm.

I’ve been reading this article Solving Calcium and Alkalinity Problems so I can get my head around it. It turns out my tank is in Zone 3 according to the article. Since normal level of calcium in salt water tank is between 400-450ppm and KH between 7-11, I have to add calcium chloride only and no more than 20ppm daily in order to bring it to normal level.

The local LFS recommended Sera Marin liquid Calcium, so I’ve been putting half a cap full every night. I add it by dripping it slowly where the pump exhaust is, that way it gets dispersed equally.

During the calcium dosing the KH can drop because the calcium and the KH are linked. I will be testing both every day during dosing so i can monitor the KH closely, as well the PH.