Cherries Jubilee

Things are looking good for the most part except for the fact that im battling fungus gnats, I've never really had this issue before. My watering habits haven't changed and it seems like they kinda just popped outta no where, I noticed because I always hang yellow sticky card. I dumped some beneficial nematodes in the soil a few days ago, I also covered the soil with sand to see if it would help, I have some BT on hand in case things get any worse. I noticed the visible trichomes making their appearance a few days ago and the buds are starting to stack, hopefully I end up with a few decent sized colas.