Leaf tips curling up during flower

Hey guys. Ive been trying to research my problem, but not finding anything that closely matches my problem.
My system
Oxygen pot ebb and flow buckets with 50 gal res ( only filled to 25 gal)
Gh flora series nutes 3, 2, 1 ratio, with 2.5/gal calimagic ( using ro water)
3" rockwool base in hydroton
Using air stones in res
Water temp is 69F
Room temp is 77-79F
I keep nutes at 5.8-5.9

Been having issues with leaf tips curling up on middle and upper leaves and lower leaves are yellowing and dropping. What do you guys think?

Oh and my humidity is around 45-55RH

You may need a feed. Its what it looks like to me.
Whats the ppm of yor res?
How long since you upped ppm?
Calcium can do some pretty trippy shit, if its in excess, or deficient. Like random leaf curl.
If you havnt upped your feed in a while, id be inclined to up your base nutes, and leave your calmag the same.
Let us all know the info of the ppm you feed, first, please.