Can't reply so replying via question format.

There actually are some sprays that are effective. At work they recently started using a sulfur based one preflower as a preventative and it's working great throughout the entire flower period. Prior to that we were using an essential oil based fungicide to treat outbreaks. It's peppermint and rosemary oil based. It got rid of the PM but didn't prevent it from returning...but it was safe to use during flower.

Growdiaries changed the ability to reply to questions with the site "update" its in quotes as it was not really an update and came with a shit ton of problems and its still not functioning as well as before and even before the site was a hot mess. I think they did this as some people who answering their own questions and others where freaking out as they thought they where cheating for a contest that evolved aorund answering questions on this site. You can also send a DM or direct message to anyone using your inbox, its the little paper airplane icon in the bottom right corner of the screen. Its called GOTM or Grower Of The Month, you can find it in the contest page here. https://growdiaries.com/giveaways Out side of all this, and their stupid update. I would recommend trying to grow Sativa leaning plants with higher resistance to molds as they tend to be a bit more airy in the buds do bud rot can not set in as easily and they like the extra heat and RH as that's where they are normally from. The other option is getting better ventilation in the greenhouse, or growing them outside of it if the RH is lower outside of the greenhouse. its going to be a uphill battle once the mold is present in the green house especially if it is WPM aka white powdery mildew as its spores survive over seasons and they are aggressive and hard to get rid of. When you feed plants Si or silicone it helps them build up a resistance to WPM, but its not fool proof. Best to get in better airflow. Spraying shit does jack all and you don't want to spray stuff for WPM in bloom. One last option is growing Autos that finish faster in the season before WPM hits. Good Luck!

The simple usage of airflow, however you can accquire it will help way more, i would personally not take something off in flowering if you dont have to. I used chargable USB fans for my greenhouse, but not on cannabis, Used it on spiderflowers, hibiskus (both flowers), all kinds of pepper which i think are pretty similiar in terms of environment. GL

You can thin it out some, just don't go crazy. You'll see some people striping their plants down naked and that's not what you wanna do. The anti-defoliation crowd on here go a little overboard with their overly simplistic "more leaves = more energy" mantra. Like plants don't loose leaves in nature, lol. Plants, like people, tend to produce more energy than they can use. People store excess energy as fats, plants store it as sugars. If we(or plants) couldn't store energy we'd have to constantly feed to stay alive.