Citrus iron deficiency or something else?

Planet Earth is 35% Iron.
Most is not water soluble.
Plants only need a few parts per million of Iron.
Yet for most C3 Carbon Fixation Photosynthesis plant species it must be organic Iron.
In my research I have identified more than 3 dozen common things which interfere with Iron assimilation!
In this situation it is a synergistic interaction between 4 of the 3 dozen.
Too high of water pH.
Too much Potassium Sulfate from fertilizer
Too much Magnesium Sulfate fertilizer & water.
Too much Copper fertilizer & water.
Citric acid 3.2pH at 1 teaspoon per gallon of water will help.
I suggest reading that other thread.
Lots of similarities.

Straight pine bark is known to remove Nitrogen from soil environments. Cured conifer bark (e.g. orchid bark) is a better investment. Ag suppliers (not big box stores) sell it in 3 cu.ft. bags.

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@Richard You said “straight pine bark is known to remove Nitrogen”
Would using pine bark fines still be a problem if one fertilizes?

After this comment, I spent a lot of time reading about container soil and read the articles by Tapla. It really improved my understanding of how water and soil interact, capillary pressure and gravity creating a perched water table and how soil particle size impacts this. Thank you.

It’s only been 2 weeks, but adding the perlite seems to be making a difference. I am having a difficult time finding pine bark fines, but according to: Growing Citrus redwood shavings would work just as well.

I am still a little confused why bark/shavings is necessary though, can’t I just add more perlite till the drainage is ideal?

Do you use the same 5:1;1 mix for figs, or just citrus?

@bigiggye For figs, I use a 2:4:1 (pine bark - not sifted, peat, Saf -T-Sord or Perlite, 1 cup lime/5 gal mix) because it is more water retentive which is what figs require.