kinda a mix of both, so i'd say k tox?
Maybe, zinc deficiency? if you don't know the breakdown of what you feed it'll be a guess even with a leaf chart. i'd break that stuff down based on label and make a more educated guess. e.g. if you find you provide plenty of Ca and Mg, you know it's lockout of some kind.
pH is another thing to check. At this point that's what i'd look into first, but do breakdown your nutes for future reference -- if you use a vege and bloom formula, even if some transition, you can have 2 lists of ppms ready to reference. (molarity would be wiser, but info on web will be in ppm)