ok I have been struggling to keep alk up but thought I was getting there with kalkwasser and some additions of 2 part. before this calcium and mag always stable at 400 to 440 and 1320. But at my last water change notice sand caking so thiught oh no better test everything again and noticed mag dropped below 1200. Now trying to get mag up slowly up and was working but when I decided to add more 2 part mag dropped again to 1200. What the heck. Should I do nothing else but first get mag up before adding part 2 or kalk?