Interesting that your plants respond so quickly to Mg in this case.
Im not sure why that would be magnesium deficiency though? When I’ve had it previously it manifests as yellowing between veins, especially in lower leaves.
I use MagPro as part of my feed schedule to provide extra Mg on top of using DynaGro and Bloom. Also her rez is above 2.0EC so I think it’s unlikely she is deficient, but wouldn’t rule it out. 