Droopy leaves, curling at tips, and now brown/yellow splotches on leaves in DWC. Not sure what the issue is

Two things come to mind... 1) nutrients too strong and 2) the biggie, 24 hour light! Your poor baby plants are simply exhausted. Nothing on Planet Earth has ever evolved to live in constant state of activity and without some sort of "sleep" every 24 hours. Changing to an optimum lighting schedule for all cannabis plants, autos or photoperiod plants in veg, of 18/6 will see them recover and return to full health once again. Your plants will grow faster, healthier and stronger at 18/6 than at 24/0 due to the fact they are getting the "sleep" they need for a healthy and balanced metabolism. 24 hour light can only be recommended by people who either don't care about their plants or do not understand the basics of how plants function and grow. Part of a plants functioning is "sleep", without it a plant will go haywire waiting endlessly for a rest that will never come. This is bordering on plant cruelty, but is never too late to change to a normal and healthy 18/6 light dark schedule. I like to think of the 6 hours of "sleep" as 2 hours to recover from the day, 2 hours to rest and 2 hours to get ready for the day ahead and this is basically what occurs during the dark cycle. Sleep deprivation is a common torture technique for good reason, it drives people nuts, no doubt your little plants feel the same! Besides, cannabis can only grow so much during any 24 hour hour period and this growth tops out at about 18 hours, meaning running your lights any longer than 18 hours is basically a waste of electricity. The 18/6 light dark schedule has been derived at through over 80 years of dedicated cannabis research and is not a random number, but a scientific fact. Treat your plants to the sleep they NEED and everything should go back on track with normal growth and a natural circadian rhythm. Lord knows every living thing needs one. The small blotches at the end of the leaves are damage caused by the leaves hitting the side of the pot repeatedly when the fans blow on them and is of little consequence. Also, make sure your nutrient solution is not getting too warm, this can cause your plants to droop as well. Hope this helps, and help your plants, they NEED "sleepy time"! Cheers,............ Organoman.