4 x 4 x 7 = 112 cubic ft in a basic tent
4" inline exhaust fan's are basically 200 cfm fans (cubic feet per minute)

with a carbon filter the efficiency of the fan drops, for argument sakes lets say 75%, so the fan moves 84 cfm.
that small fan exchanges all the air in the tent every 1.5 minutes

heaters, tower ac's, humidifiers, de-humidifiers will be the most effective outside the tent conditioning the air before it is drawn into the tent.

just my opinion, hope it helps

jj

Not sure of your exact situation but agree with JJ, it works best for me to control the humidity in my lung room (the room the tent sits in) and that room feeds the tent. But I close the door on that room to better control it. My tent also exhaust into that same room which also helps me to maintain the humidity once I achieve the desired RH.

Curious.....I've read posts claiming that running a dehumidifier in a small tent doesn't do much in lowering humidity because of the frequency of air changes in the tent.

My lung room is a living room with no doors so I can't isolate it and pre treat the lung air. In my case, what dehumidifier would you all suggest?

I have a 5 x 5 tent and will be housing 6 plants that I'll be scrogging across the entire 5 x 5 canopy so gear either needs to hang off the roof or fit below the screen and still be accessible.

I'm kind of leaning towards this one: https://www.amazon.com/dp/B0816T8CT...olid=1JZWJO8D2J3LZ&psc=1&ref_=lv_ov_lig_dp_it

I like that it has a drain hose so I don't have to continually be emptying the reservoir. I'll drain to my nute rez. It's also fairly small in size so I'm probably going to try and hang it off the roof rails over the lights. I'll try and make a cradle with rope ratchets to keep it suspended although it makes me a little nervous hanging a 30 pound machine over the plants! Just gotta make sure I secure the cradle.

I'm also thinking of making a lung box to isolate the room air and give the dehumidifier somewhere to isolate the dry air to introduce into the tent.

I calculated around 22 pints a day capacity for the amount of plants that I'll be feeding. I also have an AC Infinity T6 fan with controller 67 to help regulate temp and humidity. For now it's doing a good job keeping my seedlings going into veg within parameters but once the girls get deeper into veg they're going to be expiring a lot of water vapor so the fan alone will probably not be able to keep up with the amount of humidity the plants will give off. I'm thinking the dehumidifier will be more supplemental rather than the main humidity extraction unit. The fan should remove most of it.

I’d hang a couple socks full of rock salt or rice and see how much that helps.

Roots Ruler,
You are probable already aware of this but just to be sure, remember the drain must be lower than the dehumidifier to drain. I know you said you were planning on hanging it so you should be okay, BUT, just in case you didn't know, there are dehumidifiers with built in pumps if needed. Just be sure to buy the right one first.