Here are links to three of my favorite chemistry articles that I live by. Read and reread them to learn what you can from them. The charts and tables help a lot to let you know what is within normal range. And there is good guidance on what to do if they aren't.

You can adjust the alk/calc balance by changing the type of salt you choose. For example, Instant Ocean is typically higher in Alk and lower in calcium than most other salts. Pro type salts like Oceanic are on the lower end of normal for alk and higher in calcium. But this isn't always consistent from batch to batch.

http://www.reefkeeping.com/issues/20...hf/index.php#d

http://www.reefkeeping.com/issues/2004-05/rhf/index.php

http://www.advancedaquarist.com/2002/11/chemistry