Nute Question- 600w dwc Nirvana AK48

She does not look bad. You don't need to add extra micro's to sensi A+B. They have plenty and that's why they're not intended to be used with a calmag additive either. AN uses a lot of chelates and often the first problem to show when using them is micro disorders. Chelates are responsible for the never ending pounding of micro nutrients in to our plants. Once the levels of a certain mineral get to high in the plant or root zone then it will interfere with the uptake of other certain minerals.
 
There is no reason you should have to make a custom nutrient program to grow a plant that will grow itself, your job is to just keep it alive, healthy, and happy; not to try to force it to grow with nutes, it will do that own its own. The only thing that can force a plant to grow is light, period.
 
Okay, where ever you are with your nute strength, stop.  Shes is maxed out. She is starting to turn dark green and accumulate salt deposits of the leaf (aka burn). The stem is pointing up, or very turgid, signifying that the turgor pressure is maxed out (nute pressure on the plant) and the leaves have a slight hook which signifies that the stomata is slightly closed or trying to restrict transpiration. These are all signs to me that your plant is maxed out on nutes.
 
I would just let her ride on where she is for a bit. Using the gh micro probably just reduced the amount of chelates in your soup which lessened the micro nute pounding. imo you should be using the AN micro and you just wasted your money, sorry, may be you can do a gh 3part run next time, add a little floralicious plus (great stuff) and you'll be set!
 
A few questions to help me narrow in- What is your humidity? Low rh can cause high transpiration and cause the plant to require a lower ec. What if any additives are or were you using?The spots started shortly after you started using the sensi, correct? Do you use tap or R/O water? What is the starting point of that?
 
All and all I wouldn't stress out. She looks nice. Good job so far.