You need to get a running start and then stay on top of it. Start with serenade - spray once every two to three days for three times....that would be when the plants are young.
After that spray once/week with a mixture of 4 or 5:1 water:milk....yep, plain old milk. Works great, not good for PM and not bad for you! You will want to keep that up at least thru veg. Flower is a little trickier since you would prefer not to spray buds...but you can if you need to. You can do this with AACT as well but milk is easy and effective....of course, mixing it up a little is good - milk one week, AACT the next, etc
Use a fan if it's in a dead air space. Don't let it get too thick with leaves, etc...thin the inside a little...and good luck.