77 questions... Some of you folks.. It's like you expect other people to grow for you. You could put more effort into the question then "Watts this"... So Watts this? A lazy person unwilling to figure things out for themselves :).
Why woulg you go to 1400ppm . Go back to 1000 if you are just stsrtingbto flower. You need to work slowly yiur way up to know if the plant can handle it
Looks like you probably had a pH flux then. But my guess is it has already been corrected by the looks of things. Old damaged leaves won't get better. Look to new growth to see if a problem has been corrected. 🤘😤