What nute deficiency is this and what can I do to fix it?

[Major PITA]

I've fed cal-mag both ways (with and w/o nute's). I do prefer to give it alone only because it boosts the EC of the solution quite a bit. When I feed at 800-900 PPM, the cal-mag takes it up to something like 1300 if I remember correctly. If you are aggressive at feeding, I can see it getting your solution up around 2000 PPM

 

[fanleaf]

Not trying to step on fan leafs toes, but we always feed nutes and add calmag. It hasn't had an I'll effect on our plants, but it makes sense to do it separately. I'll talk to nis to see if he wants to change it up. We forget to add the calmag at times so we use it and flowers kiss as a foliar spray and it works out for us. Have a great day guys.

Not stepping on any toes here Canna.
I know lots if not most do feed at the same time as adding CalMag with no issues. Hell, I will probably still do it from time to time myself hehe. I was just thinking that while the OP is having issues probably due to pH and or salts it's probably better to only do one or the other especially until it's fixed up.