makin it kinda tricky to answer your question but ive recently changed Calmags and now i use a calmag plus with kelp and iron during veg with a (4-0-0). for flower i have a real low Nitrogen @ (1-0-0). i also have magnesium sulfate (Epsom salt) but i prefer calmag throughout the grow/flower. i believe its the Nitrogen you want to cut out in flower
I think balance is the key, to much of one nutrient or a combo of too much can lock out another. I use a lot of cal/mag through flower and I almost always see a Potassium Deficiency in the last weeks of flower when I really want it to take in more so I will use a lot less next grow
This is a good article but not exactly an easy read for me. I would like to find a chart that is easier to read.
I use sensi cal mag through out the entire grow. CPW has a good point about the balance because I get some signs of potassium issues in late flowering to. I have already started backing off with my last grow but I am going to pay better attention with this one.