One plant developed a deficiency, what is it?

Hi all, one of my plants has this deficiency and now the big fan leaves are starting to die or become affected, just looking for speedy advice, what do I do?

Thank you so much!


Looks like magnesium to me.
Do ya have any Epson salt?
Google magnesium deficiency and see if the pictures doesn’t match.
Magnesium effects older lower leaves first and looks just like thatvwith the yellow pattern.


I agree, looks like it needs some calmag.

Nutrient Deficiency chart