After A-man suggested sulfur, I did a bit of reading on the subject. From what I read, it's a fairly rare def. Also some of the photos I looked at did not speak sulfer def to me, some kinda did. I also trust Aman a lot and so I went with his recommendation, worst case scenerio, I have to change out the res if things did not bode well. From what I could tell, she improved and at the very least, did no damage.
I have read that sulfur is an uncommon problem because of burning coal dumping it into the atmosphere. Not sure how well that relates to indoor grows tho.
You are right to trust aqua and I am not trying to second guess anything here. This could be something different.
That appears to be your apical meristem. Correct me if I am wrong.
That should be about the most healthy part on the plant. It looks light green and tiger striped to me, but some of that could be in the camera. Regardless, If this is the newest highest growth on the plant, it should not be suffering any sort of mobile nutrient deficiency while those bottom fan leaves are nice and green and perfect. Boron (B), Calcium (Ca), Copper (Cu), Iron (Fe), Manganese (Mn), Molybdenum (Mb), Sulfur (S) and Zinc (Zn) are the immobile, or partly immobile nutes.
This is the label for Flora Micro
It's basically the immobile nutrients plus some N and Potash.
I suppose one way to look at this is the ratio of Micro to Grow should be adjusted based on the symptoms and amount of N needed, and if the symptoms seem to be immobile, Micro is your best friend. But if you are in danger of N tox, you need to take Grow out at the rate you up Micro.
Also, adding epsom will not hurt, and may help! Sulfur is not in Micro, so, OK I'm babbling.
