Pest/deficiency id - Brown spots - Cal/Mag?

[steppedinds]

only the tops of 2 colas are affected and are from the same plant. i'm thinking cal/mag but just wanted to get another opinion. been using 2.5 ml per gal of GH CaliMgic. thinking of doubling? waiting on my phone to charge so i can use the microscope to see if i see anything...the wait is killing me

 

[jhfhklsnhfldk]

I know it's been a while since the post, but how are you doing with this one? This looks like calcium. Adding more calmag may make this problem worse. A very simple test to rule our cal def, is to expose part of an effect leaf, that is normally not in direct light, to direct light. If the rest of the leaf begins to freckle, it is most likely calcium. If you are cal def, and in good soil, you likely have ph issues. For me the fix has been a good flush, then start back with nutes and calmag.

 

[steppedinds]

ph is likely the issue. ive got one of those cheap digi readers and im always scared to add too much ph down. ill try to keep it closer to 5.6 from now on. very good advice. thanks a ton