Now I do. With adding the cal mag you are adding lots more N without adjusting your K to keep the correct NPK ratio of mega crop. I use protekt 0-0-3 to rebalance cal mag 2-0-0 if needed. I would stop the cal mag and jump the MC up to 5.5gm-gal.
Taking clones during flower can cause problems. Cloning is the most stressful time a plant goes through add that with the reversal to veg. It can be done but then you worry about the possiblity of the plant turning hermie.