Humidity problems.

[MischiefGrows]

I just started week 5 of flowering today and for the past 3 days, my RH has been hovering around 60 with the lights off; Lights on i can get it down to about 45. I have a 30 pint(?) LG dehumidifier that i bought months ago and have just now been able to put it to the test. I used it about a week ago, and the humidity in my whole house went down below 30 for a few days- so i thought it was working too well. Guess those days were just very unhumid outside? I've started to pay attention to humidity forecasts for my area and it seems i live in a relatively humid region- 30-60%, mostly around 60 for the past few days. I haven't seen any signs of molding or mildew or anything strange yet, but i know it is going to be crucial to get the RH back down to under 45%.

I am running a passive intake room, so i wonder if possibly the air that is being dried up by the dehuey is just being sucked out and replaced with outside air that is humid (RH possibly seems consistent with outside humidity).

A little about my room:

10 x 9 x 8
4k watt (8" cooled hoods- 2 cool tubes, 2 blockbuster's)
I have two 8" canfan's pulling air through the lights and pushing the air outside (into the garage)
---->Room---->Light---->Light---->8"fan---->garage
---->Room---->Light---->Light---->8"fan---->garage

I also have two 16" oscillating fans circulating air around the room. ( i had these positioned just above the canopy to focus on the heat coming from the lights. now, they are directed a little more onto the tops of the canopy's hoping to keep the buds from absorbing too much of the humidity)

I have tried to position the dehumidifier inside of the tent, and i have tried putting it just outside of the tent, hoping that it would dry the air being pulled into the tent and the old humid air would be replaced by dry air- this has not worked.

I would suck it up and go out and get a larger dehumidifier, I am just curious about the air being exhausted. One thing that may be possibly hindering my air flow- whether it is effecting humidity or just my temps- is the way that the ducting from my two fans converge and exit into the garage. I figure my best way around this is to make another hole in the drywall for a dedicated exhaust line for both fans. I try not to cut holes in the walls as much as possible but its seemingly avoidable at this point. I would like to completely re-do my room. A little larger, and a little simpler- but thats gonna have to wait til this crop gets chopped.

Any comments, idea's, suggestions, help in any form would be great.

 

[MischiefGrows]

Also, I am using coco- 5 gallon smart pots. There are no reservoirs or anything else that would be drawing or creating extra humidity in the room (that i can think of at least).

 

[mayonnaise]

45 percent seems pretty low I run between 50 and 60 and have had almost no mold or mildew problems. I've heard of people running much higher than that with little problems, but i'm not that brave. If you are running a really dense strain you can stress a little more toward the end but don't trip out about it in the middle of flower so much. IMO keep it under 60 and good air flow and you should be golden.

 

[CelticEBE]

I have more experience with sealed rooms, where I run co2 and keep my humidity levels at about 70% until the last two weeks when I drop temps and keep my humidity around 50%...

I think you should be fine, just as long as you have adequate airflow.

 

[cctt]

When you're ventilating a room it tends to make any other kind of climate control (AC, humidifier, dehumidifier, CO2, etc) somewhat useless as only a very large system would be able to keep up with the fresh incoming air. And that would just be a waste of energy.

Your RH levels do not sound unreasonable to me.

 

[caveman4.20]

Filter passive air if you can and run the dehumidified air through canopy.