youve got 2 identical threads in the problems forum now....

usually problems are ph or nutrient related.

for a hydro rig, your ph looks fine, maybe a smidge higher (6.8-5.3) will be usefull, but probably not your problem.

try reducing nutrient levels slightly as your first problem sounds similar to a burn

your leaves curling up is sometimes related to Mg deficiencies i believe (check first though), and may be corrected with a light epsom salts foliar spray. (confirm with an expert first)