Loving my new grow space and the way I can control climate, however, looks like I still have some tweaking to do. When I started a dry run I found that temps soared and humidity dropped to the 20's. I added a humidifier to get humidity into the 60's for veg and my temps dropped to the mid 70's, with 4" exhaust fan turned down as low as possible. Now that I am in flower I have lowered humidity to the upper 30's and temps have climbed to 80 with exhaust fan full speed. I never knew humidity had such an effect on temps. Bumping humidity up a little to get temps back in the 70's. Now planning to upgrade to a 6" exhaust fan when I need to order a new carbon filter. Hopefully that will be the final piece to the puzzle. Oh what a tangled web we weave when we decide to grow our own!!