Which do I dose first... Alk or Cal?

[nicholasb]

Just remember for every 1 D.K.H you would lose just 7ppm calcium, so you might never see much of a drop in calcium, with a standard hobby test kit.

 

[Jim.mer]

Before adding anything, You should know your values, I would ad directly to the display right in front of a Power Head. Test once a week. Ad Alk and Calc nightly. When you test for Mag. If it's low add. Test again the next day. Lower than 1200 for Mag, It's time to Supplement. My schedule was to make 3 litres of each, Add Calc and Alk til the bottle was empty then add the entire bottle of Mag supplement to the Sump in a high flow area. Test the next night.