It could be something as simple as the genetics of the plants themselves. Ive also had this happen from trying to FIM my plants, and the other time was from the plants genetics im guessing.
Hope this helps
BigBudE
The wrong Ph will twist the new growth. Over watering will make all the leaf droop.
Good chance what you see is caused by insects if its isolated. (not happening to all the leaf) Aphids like spider mites need to be killed in two steps first kill the adults the about a week later spray again to kill the eggs that have hatched but are still juveniles and haven't laid any more yet. Here is a good link to read, LINK
That hard to say, depends on how fast it drains. I guess the best way to know for sure is to dig a hole next to it and see.
I would go down a little over a foot and see if the soil is damp.
get calmag if using RO
a little tad bit, but its also happening to new growth.. so I really dont think thats the problem. ill take pics right away. I try to water with a 23oz bottle on each plant (pretty small amount) everyday now. but today ima skip it in case its too much which i really doubt. pics will be taken of whole plant and an example of the problem, plus new problem, the side of a leaf is turning black as if burnt..Did you splash the feed on that leaf? Could be burnt from water droplets being on the leaf. Could be burnt from the feed water eating the leaf