Thanks for all of the replies, guys!

J Dog - My PH on all of the soil is about 6.3-6.5 right now, and you're right. I'm almost 100% it's overwatering.

Justaseed - Are there any suggestions you have? I already have lights pointing at the fans and cooling them down as well as an oscilating fan and that A/C unit.

Herbus - I use ST about every other water, is this still too much? The soil I use is a mixture I created using bag soil, 30% pearlite, a little bit of sand and sphagnum rock.

The plants are definitely perking up since I stopped watering them so much and started letting the soil dry out a bit more. I also used a few chopsticks and made sure the soil was getting enough oxygen to the roots.

I'll post pics as soon as they go on their 23/1 tonight!