That's exactly what we are getting at
@Homer Simpson . The Megacrop should replace the Calmag by increasing the dose, however if you go too far outside the MC limits, like I did, then the N ppm becomes too high for the plant, most likely causing nute burn.
I was using Sweet Candy, which has a K value of 16. So we think that was locking out the plant from uptaking the Ca.
I couldn't advise on the BudExplosion as GN does say to use it during the plants phases, veg and bloom. I can't try it on this grow as I have a comparison going already, but next time I will.