looks like a case of either root rot or nute burn, almost looks to me like they have hermied.
Your temp swing is of huge concern too 66 to 82 is crazy swing too cold the humidity as well is far too low.
from this picture I am seeing drooping leaves yellowing necrosis and curling your plants are in bad shock.
What you need to do is get control of their environment keep temp between 68-78 humidity 40-60% water only when needed with ph’d water 6-6.5 do more home work. Not trying to sound like a douche but if those plants recover would be surprised if they didn’t go male or herm on you.
You are mother nature in your grow room and from what I am seeing you aren’t sure if it is summer or winter? Happy plants get a 10 degree swing from night to day enough moisture in the air they don’t think they are in a desert.