Parameters for growth look fine, hmmm, oxygen depreviation of rootzones, oxygen itself is kinda like a nutrient in that it needs to exist in the rootzones in order for the plant to perform photosynthesis.
Your soil has no perlite or anything thay would give it the air pockets its needs, soil looks very grainy and fine meaning top watering could compress the soil especially if you blanket feed.
Leaves look wrinkled and fat, wayer it building up in leaf as it's not being released efficiently through transpiration.
Many reasons this could happen but if I had to guess I'd say it's a breakdown in water movement. Big plastic pots with little to no oxygen pockets to play with.
Right off bat you need a pH possibly a ec reading to get an idea of where she sits, worst thing you can do is add more salt minerals until you know it's not ph or rh.
When transpiration becomes crippled wayer doesn't cycle if it doesnt move from the plastic pot it will stagnate causing eventual salt build up if you continue to feed, what goes in must come out.
More moisture is going in than is going out, most likey due to a breakdown in water movement.
If you had a super dry arid environment and needed a way of retaining moisture plastic would be a option. You run 80F+ in a pot that's unable to breathe. Moisture will only uptake or evaporate, evaporation is not a option for 90% of your pot.
This is more critical in warmer climates because at higher temperatures water holds less dissolved oxygen (DO).