1 Wilted, 1 Healthy??

Nitrogen/nutrient toxicity would be my diagnosis, as well as being exhausted. Each plant is a law unto itself, no two plants will ever require the exact same conditions/feeding/watering. Also, 24/0 is not what plants need, they need sleep/a dark period to complete their photosynthetic cycle and have a correctly functioning metabolism, but the good news is that it is never too late to switch to 18/6. Cannabis can only grow so much during any 24 hour period and this growth tops out at about the 18 hour mark, meaning running your lights any longer than 18 hours is basically a waste of electricity, therefore even 20/4 or 22/2 or 19/5 or 21/3 is also pointless. At this stage I would be giving just plain water for the next 10 days before resuming feeding with half strength nutrients. Trying to flush the soil with excessive amounts of water will just make things worse, as this will just release even more nutrient salts from the soil, increasing the nitrogen/nutrient toxicity effect.... possibly killing the plant. From the very green colour of your plants, I would guess you are possibly feeding them too often. In soil, you should be feeding every third irrigation, that is ..... plain water/plain water/ feed/plain water/plain water/feed, so that your plants are only getting nutrients every 10-14 days (roughly). Also when giving water, you must give enough until there is run off/water coming out of the bottom of the pots. This serves two purposes, firstly, that the substrate is moisten from top to bottom, which is vital for root growth and secondly, it helps to prevent the build up of nutrient salts in the substrate/soil to toxic levels, which seems to be what has happened with your plant. Also watering deeply and thoroughly every few days is much better than watering little amounts often, which just causes salts to build up. Waiting until the top 3-5cm have dried out again is when you know that it is time to water your plants again, deeply and to run off. I have found that half strength nutrients is usually plenty strong enough, especially when it comes to autos. Lifting the light while this plant recovers may also help in its quest to resume health. Hope this helps, Organoman.