Maintaining VPD

VPD at night is less of a concern. you still want to avoid HUGE deviations, but the stomata are closed at night and transpiration is minimal. Some respiration (o2 released) is happening but not a ton. Think i read you want less than a 0.4 swing from night to day, but again, the daytime vpd is 10x more important to worry about. That's when you want to control rate of transpiration. a constant exhaust running at proportionally lower cfm will be the same electricity and a more consistent effect over time. This would only be a bad idea if you are also supplementing CO2 as that would throw money out the exhaust, though you should not need an exhaust in that context, either. You are micromanaging a bit, but there are things you can tweak that just passivley happen, so it's not like you are creating daily maintenance.. fine-tuning things is a good thing. you take some notes and skip these steps in the future, so it's not like it causes extra effort for you to get the environment humming -- relative to the controls you have. Might as well make the best use of your setup. e.g. i just bought a new, bigger dehum. it functions slightly different than the last and can keep up which makes a big difference, too. I had to monitor the temp/rh prob data for a few nights once the canopy grew in and adjust the hygrometer etc etc... I know that on colder nights i need to keep doors closed near my furnace's thermostat and on unseasonably warm nights i leave those same doors open and it helps maintain better temperatures. Nothing wrong with knowing how to work the 'levers' available to you.