How good is your water to start with? Is there a chance of chlorine in the water?

One problem is it looks & sounds like under watering too. Strange

Remember clones inherit the age of the mother so after the first week of switch you should only use 1/2 strength the first 5-day's or so then bump it up. You are using CO² and pushing them but it sounds like you may not be giving then enough nutrients to keep up with the rest of the push.

I use Epson salt in the res tank not as a foil spray. Moist leaves with just Ph adjusted water and maybe a little B1 is fine in vegetation cycle and the first 2 weeks of flower but after that you run into chances of bud rot. When you have a spare buck or 200 lying around you should think about a sulfur pot. If you have mold that will kill it fast and not harm the plants or the taste.

You may want to put some kiddy play sand on top of the dirt for your plants; it looks like there may be some roots on top of the soil.