I saw that the topic did stop… like to open it again.
I’m using the book : “Nutritional Disorders of plants”.
In Europe, Russia, east Europe and also Scandinavia it’s THE bible to find out what’s the problem if you notice one.
It’s Edited by Werner Bergmann.
ISBN 3-334-60422-5
Florida 33442-1705 USA.
As far I know it’s only to become in English.
SpeesCees
And then you should lissen this very Dutch song about NEDERweed !
We were the first down there !
Neder means… down under inHolland where I’m coming from ! 
Cannabis Sativa Hollandia… YEAHHHHHHHHHH>>>>> !
Looks like it is out of print… It will be hard to get…
The only similar book I’ve found available in PDF is this one:
A Visual Guide to Nutritional Disorders of Tropical Plants
http://ageconsearch.umn.edu/record/114812/files/61.pdf
Also
http://ceac.arizona.edu/sites/ceac/files/pls217nbch9.pdf
And this
http://www.horticulturebc.info/labreviews/pdfpests/Abiotic%20-%20Nutritional.pdf
are pdfs of some good nutritional disorder reading. . .not on cannabis but it’s still a good read
Yeppppp… that’s the one Joe !
If you can’t find the problem in this book… then you better use your time better.
SpeesCees