Ya I’m going to have to dig deeper about this subject it’s really taking things to the next level in terms of environmental control. So wut I got from it is the lower RH set for night will increase nutrient and water intake thus making you plant grow faster? So I’m in veg right now and I like my RH at like 60-65% so at lights off I should set it to like 50-55? Then bring it back up during the day back to 60-65%? I know you can get really deeper into it but is that kinda wut yours getting at?
Kinda but not for that reason. Lower humidity at night is because the plants don't transpire much and the humidity has little effect on uptake for that reason when the lights are out. The lower humidity creates less chance of condensate. It's not that humidity the same is bad it's just not needed so no need to run your humidifier and waste power and water.
You can absolutely run the same humidity day and night... just to make clear it's just not needed. What you do need to worry about is the dew point.
Decent air exchange and airflow through the plants is important and humidity only becomes a real issue when its to high in most cases. So if yours low it's not likely to cause you issues.
While VPD is a good tool the key is just don't hit the dew point. It's not as likely to make a huge impact for your grow results at a newer skillset or without very high light.
While I am all for VPD there is a limit to its importance and impact so don't go all nuts trying to make the perfect humidity.... you just need to keep it in a decent range. Generally 40-60% is a good place for most growers.
I just wanted to link it to give some explanation on how and why. Not get you to panic and go balls deep buying a bunch stuff that's going to make little impact.