Best dehumidifier for a 4x4 grow space?

hello everyone
I recently bought a grow tent.
I plant to grow 1-4 cannabis plants.
what is the best dehumidifier set up for a relatively low cost?
I got a tiny humidifier, space heater, a/c, and I am in need of a dehumidifier. I’m using a led sf4000 and 4’’ ac infinity duct fan.
any suggestions for the dehumidifier situation?

I don’t know about dehumidifier sizing but I’m gonna bet your AC Infinity is way too small for a 4x4. I just set up a 4x4 and the math said that I needed at least 400 cfm so I got an AC Infinity T6. Proper air movement should help with your humidity issues.


yea… it’s a 4x4 grow tent.
I haven’t grown anything in it yet.
It works well with controlling the temperature of my space heater but the humidity is always above 60% and during flowering stages and drying and curing it cant be that high. I plan to just run the t4 with a 4 inch carbon filter.
I will wait and see before I make any returns. I don’t know that it will help with the humidity i am assuming i need a small dehumidifier in the tent.
humidifier/dehumidifier to control the moisture thru out the plants life.
i also got a space heater and tiny a/c for the temperature.
also a water temp controller for the hydro reservoir.

Dehumidifier size will vary based on conditions. Some people can even get away without using one at all. Your best bet is to get one large enough to get the room intake air comes from dialed in.


I second this! I use large room one in my lung room. And i do have one in my tent from time to time on a controller. Mainly only in last week of flower and for drying to be dialed right in. As for your exhaust @mylestrades the t4 will work but you’d be much better off with a larger unit. Can keep that fan too as a back up or for a second veg tent one day…just some food for thought. You’ll wish you had the bigger fan come flower!

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Have you test ran the t4 with filter installed? If so, you will probably be good. The small mixed flow fans don’t seem to do as well with static load. My 4" would just barely get by in 5 ft² space with 160 watt light once filter was installed. I upgraded to 6" and run at less than half power.

i’m in the process of returning it right now in exchange for a T6.
I think that will be better. but will a T6 eliminate the high humidity issue?

I didn’t get a lot of air coming out the vent even when it was on the strongest speed so thats why I am figuring exchanging it is the best solution.
I am still concerned about the high humidity though.

If you place a dehumidifier inside your tent it will raise the temps.

As dbrn32 said, it’s best to condition the air coming into the tent.

this does the job

I air condition the room the tent is in. I use a 4” inline fan 205cfm. The plants themselves produce a lot of humidity so the constant airflow will help with controlling it.

my completion time line has been extended.
I will have to get a dehumidifier at some point in time.

That’s a $300 dehumidifier ,WOW

With dehumidifiers you get what you pay for most of the time. Best to get a large room one that is 200-300 range new. Or find a good used one for 100-150$. Or buy a portable aircond…then sock it off to the tent and get that warm air outside or into another room. Then in winter you can heat your house or a room with the exhaust. It may seem like a bit of money now but you’ll make it up when you are happy as your product gets better and better and hopefully bigger! Bit by bit you’ll build your arsenal for growing dank! Good choice on t6, you will be able to dial all your prams in better with the added air exchange capabilities @mylestrades

its worth its weight as it contributes to my almost mege-yields

for a couple more bills he could get a really good all in one, Air Conditioner, Dehumidifier, & Heater , this handles my 70x50 basement


They have small dehumidifiers around 70-80$
I don’t want a big 1 because I only have a 4x4 space to make use of.
I’m trying to buy the best quality of equipment I can afford but I don’t want to spend money on things I don’t need. I will see where i’m at when I have the ventilation up and running.

@mylestrades I wasn’t asking you to buy a 14,000 BTU tri unit LOL. I was just making a point . Some of these guys are growing on larger scale. So if they purchase a $500 dehumidifier and get 1/2 oz increase per plant because of it . The unit paid for it’s self. But everyone doesn’t have that type of money

For sure! But if you can by a big one you can use it for the larger room that your tent sits in. Which will bring down the rh in your tent. You can set your fan to blast full if it hits an rh that you set as too high…then is will ramp back down to your normal set speed…then you free up space in your tent…

will it absorb moisture outside of a closed tent?