Read this. Then I encourage you to further look into information on it. What I don't cover so much is that a warm dry light period with a humid dark period is a recipie for disaster.
You can run 70% light on if you like with good airflow. The dark period is where most growers have an issue and don't even know it. As the temls drop humidity spikes and they get condensate. Poor pruning and airflow are equally to blame. Pay particular attention to the hr or 2 following light out. And keep the humidity down or equal to your day period. I can explain more if your interested on the microclimates and how they lead to bud rot etc.
But start here. It will give you a decent basic idea of how tenls and humidity work and affect the plants.
Ok i was gonna sit down and write out a whole article but i have been lazy so instead instead I'm going to copy paste because im lazy. This is not my work so let start. You may find this very long but its worth the read. Some may want to skip ahead. I have added here and there to what i feel is...
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