Hi all: please help with what could cause leaf curl and wilt on newer leaves only, see pic. of green bean plant. Beans are 1-3 inches long and have looked healthy up to this point. Growing in perlite, dwc with air stone, outdoors with intermittant fan for cooling...temps in hig 80's. PH is 6.0. EC 1.9. roots are off white. Thanks for any help you can give. Will try to send pic with this post.