Molybdenum deficiency: Solved! (?) [Plus a lesson to learn]

So I was having a lot of trouble with identifying this plant's problem and I think I've finally done it! I was having trouble with yellowing leaves. I tried foliar spraying with cal-mag-iron (plus supplementing in water) and it did nothing! Thought it was nitrogen deficiency and now I'm pretty sure I've got the right answer: molybdenum deficiency.

The telltale clue for me was the pink on leaves and pink on buds. That got me doing more digging and now I'm convinced. Pictures attached for those more experienced to concur. Apparently this deficiency is rare, but I learned a lesson. I thought I was being smart by using lemon juice as my pH down (and several users on here even said they use it with no problems), but upon doing more research, apparently citric acid and molybdenum form a complex effectively locking out the molybdenum from the plant (https://www.tandfonline.com/doi/abs/10.1080/15533170802371323)!

I will be buying pH up and down, raising the pH, and hoping for the best. Couldn't find any affordable molybdenum meant for plants online. Of course I would run into a rare deficiency on my first grow. Sadness. Hopefully my ladies can be saved

What's your grow media, nutrients, feed/water sched, ppm/ec, pH, temps, RH, light specs and distance.

If you're using a complete nutrient line that has all the micros, you shouldn't be getting Mo deficiencies. I've never heard about the citric acid - Mo issue you posted, but I've used lemon/lime juice and straight citric acid a whole bunch of times without that problem.

Tracker said:

What's your grow media, nutrients, feed/water sched, ppm/ec, pH, temps, RH, light specs and distance.

If you're using a complete nutrient line that has all the micros, you shouldn't be getting Mo deficiencies. I've never heard about the citric acid - Mo issue you posted, but I've used lemon/lime juice and straight citric acid a whole bunch of times without that problem.

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It's just top soil (amended with peat and drains very well), Miracle Gro, water about every 4-5 days (when top 2 inches of soil are dry), recently got a TDS meter so I don't know about that part, pH about 6.2, about 74F for temp, Humidity is about 50%, light has been titrated to 50,000-60,000 lux. I had been doing 1 tsp/gallon for the Miracle Gro but plan on titrating it up if necessary once I can start using the TDS meter. The Miracle Gro has Molybdenum in it, but it's definitely that because of the pink leaves/buds (looks exactly like pics online of it). Perhaps it's not from the lemon juice, maybe an under dosing of the nutes, but I'm done fucking around with the lemon juice after reading that

jfarrismu said:

It's just top soil (amended with peat and drains very well), Miracle Gro, water about every 4-5 days (when top 2 inches of soil are dry), recently got a TDS meter so I don't know about that part, pH about 6.2, about 74F for temp, Humidity is about 50%, light has been titrated to 50,000-60,000 lux. I had been doing 1 tsp/gallon for the Miracle Gro but plan on titrating it up if necessary once I can start using the TDS meter. The Miracle Gro has Molybdenum in it, but it's definitely that because of the pink leaves/buds (looks exactly like pics online of it). Perhaps it's not from the lemon juice, maybe an under dosing of the nutes, but I'm done fucking around with the lemon juice after reading that

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I've been using ascorbic acid for pH down. For easy to use dry nutrients GH Maxi works well for my base. MG doesn't get much love here, but I've used it in the past during veg.