regarding humidity I'm pretty lucky I can keep mine around 50rh start to finish if I want but if I have just seedlings in then I use my humidifier to up it a little but soon I'm looking at maybe upgrading my 4x4 tent as the zips are a little fucked and it was a budget tent to begin with and I already bought an upgraded 6 inch
AC Infinity CLOUDLINE S6 Airflow: 402 CFM so a more powerful than my rvk 125-L high power
Systemair RVK 5" 125-L (High Speed) 323m3/hr plus its got an 8 speed controller and its an ec fan so much quieter as I picked it up at a bargain price