Cheers for the tip, Wolverine. My trace elements additive (again, non-organic) contains this but I have purposefully backed off using it for a while to make sure there is no trace elements toxicity.
My organic grow succumbed to the nasty synthetics, at least I will save my crop... I hope!
Interesting thread in the general grow area on the same topic:
https://www.rollitup.org/general-marijuana-growing/424505-nutes-cal-mag.html
I posted in there, too.
Seems like many, many people encounter Ca and Mg deficiencies, if there is a sticky on the topic I have not seen it.
The BioBizz range should come with a huge label on it reading: ALSO GET DOLOMITE LIME! Meh