at different stages your RH would be at different levels, veg I run RH around 75-80% w/ temps between 89-92 degree's as plant starts to flower I back down 5% once a week on RH (after bloom already underway) by time the plant ready to finish your rh should be down around low 30% or right around there, I try getting mine down next to nothing...BTW, what you will be using for co2? a burner/tanks/bags? a burner does not work like a co2 bag or tanks would, just so you know... if using a burner you will want a fan blowing from top of tent down toward plants, if using tanks or bags, then you want fan at lowest point blowing upwards... feel free to ask anything related to co2, I'm very good with it and have a lot of knowledge in this area...