multiple problems multiple plants! Help!

Would cut the light to 20/4 at the most. There is no information available to really help without knowing all growing conditions etc. Why a well filled out diary can be helpful.

Probably because you are growing with 24/0! All plants, cannabis included, NEED sleep to finish their photosynthesis cycle and for having a correctly functioning metabolism. Without sleep, they are being pushed beyond their limits. Only people who don't understand photosynthesis or how plants function could recommend that you grow your plants for weeks/months without sleep. 18/6 is optimum, anything else is just unhealthy and greedy. Besides, cannabis can only grow so much during any one 24 hour period and this growth tops out at around the 18 hour mark, meaning running your lights any longer than 18 hours is basically a waste of electricity, on top of being unhealthy for your plants. The myth that it is ok to grow at 24/0 needs to be erased from history asap! However, without pictures of the problems, means any answers more in depth would just be a guess, but whatever you do, go to 18/6 ASAP and give your plants the sleep that they NEED. Recovery may be possible if the damage hasn't been too awful. Hope this helps, Organoman.