Coming into week 2 of flower and the humidity has hit 72% temps are 77f and 70f in side I currently have aircon running, a 70 pint dehumidifier, 4 fans and a 250/500cfm 2 speed exhaust but can't seem to get it down the problem is the outdoor rh is 89% at the moment. Anyone have any ideas
I live in the tropics, sound like you do too. It's shit for growing. Here's what I did (you wont like it) Seal the room, install A/C, dehumidifier (rated at 2x the plants daily water use) and CO2. There's little point treating air if you still exhaust, are you? Edit - sorry , should have read better. If your incomming air is 80%, you're screwed! See the above.
Keep the air moving. I seldon worry about RH until about the 4th week of flower but have had to fight similar.
I actually keep my RH around 70% until week 6 of flower and temps 80+ because they like it when you add CO2
if in a tent in a bedroom, close window and leave dehumidifier on, leave intake fan blowing on canopy as well as other fans