You shouldn't have calcium issues when using Herculean Harvest so using NFTG never needs calmag. However, if you do need more magnesium, refer page 22 in the bible about Demeter's Destiny, If you actually need more magnesium, Mag Amped is recommended with NFTG. Excess K can interrupt uptake of magnesium.
Here is the same plant. I didn't end up using calmag this run. Added Photo plus and Ful power with most of the netar line. Still a few more weeks to go