I cleaned the garage last night and there hasnt been drywall dust on them in days. The drywall dust wasnt coming from the inside of the room it was getting sucked in from the outside.
I need to check my run-off though, as there was quite a bit of drywall dust landing on the soil as well as the plants.
You should definately go get a real nice ph tester and check your soil and water etc. The ph being of could cause nute-lockout.
Im very interested to see how these plants come out. Very nice setup