Mañ'O'Green has it right. FloraMicro takes out a lot of calcium before anything else, so you can either supplement with CalMag if you have it already, or you can switch it out for regular FloraMicro. That being said, contacting GH is also good advice; they're actually quite nice whenever I've emailed them and it's possible that you might not need to spend any extra money.
@Mañ'O'Green: We have that awesome spreadsheet you made, but we haven't put it up yet. It's definitely on our 'to-do' list for sure!