Molybdenum deficiency can occur. So can copper, iron, zinc and yadda. Just checked 3 brands of nutrients I have at hand. Envy hydroponics dry (copy of Jack's) has moly. So does AN Jungle Juice Micros. But AN Iguana doesn't. Having used it on an entire crop last year in Sunshine 4 and tap water and never seeing a hint of it I always wonder. Even if the color is textbook on shade and pattern. Like I told you I have chased "deficiencies" that ended up genetics. Black cannabis. But the buds are green. Black leaves. Started out purple cool l. Then black margins creeping in until they were black. Blew me away. Alien genetics or something.