First grow, Aeroponic, AK48, 400w HPS 2 days short of 5th week of flowering. I have lots and lots of the white pistols and lots of different bud sites, leaves are Green, no mold cant see any bugs under a 4x magnification, temps are kept between 65F and 78F. humidity is so low its not regestering on my digital temp/humidity gauge. some of my leaves have bend in half length wise but that started 5 weeks ago and its only a few and has never been new growth leaves. 2 days now I have noticed the tips curling under which is my big concern. I think its a P problem (NPK) from what I have read on the site so far but I have to put the question out there since Im half way through Flowering and dont want to lose this lady. Anyone know a reason why the tips are curling?? Please let me know I want to cry its my first major concern since I started the grow. I have 5 White Rhino girls veging ready to go as soon as the AK48 finishes. There has been one change I made and that is I went from Technaflora B.C. nutes to Fox farm using only the big bloom and tiger bloom. ppms droped some but were very high with BC. 2200 ppm but the plant seemd to love it. like I said no signs of stress or probs. ppms with Foxfarm is 1100.