My RH is at 20 ... what is recommended??

Thanks all great ideas. im gonna to try the sponge deal first. its less costly right now. until i get another exhaust fan, i am leaving my door open to control my heat issues. with this being said, will i even be able to mess with the RH. i included a pic of my room.

CaliMedicated said:

Thanks all great ideas. im gonna to try the sponge deal first. its less costly right now. until i get another exhaust fan, i am leaving my door open to control my heat issues. with this being said, will i even be able to mess with the RH. i included a pic of my room.

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I'd agree that a pump and air stone is better than a sponge, but I was going for "cheap and now" suggestions. It might be harder to fight off the influx of dry air though if you don't have a closed system with controlled air flow in and out.

To raise the RH in a closed 4' x 4' x 6' room at 80F from 20% to 60% you'd have to evaporate about 5 teaspoons of water (25 grams) with everything else staying constant. If the room is open and the air is exchanging with dry air you'd have to keep this up with whatever pace the dry air is replacing the wetter air. This might be difficult with just an open door and with fans blowing around inside as you have in the photo.

But the previous poster who said not to worry about it may have the best answer. I had only about 30% RH in my veg closet for 4 weeks (sprout to preflower) before I got my "darkroom" tent in place and didn't see any problems at all with my plants. Keeping the temperature below 85F seems to be more important.

If your grow area is not sealed you will struggle to control the RH, it will always be the same as the building or surrounding area (give or take a few percent). Too low a humidity is less of a problem providing the plants have access to water, Whereas too high a humidity can cause mold problems during heavy flowering. So basically if you have a fairly low humidity of 30 - 50% then that should be fine, just watch it doesnt creep over 50% when the plants are in full bud.

i put the bucket with the sponge and its around 25 RH. ill leave it in there, but i agree i need to worry more about the heat. so i think im going to put a second exhaust fan in.

so things are getting better in my grow room. im at at 30-32 RH and around 83-85 degrees. i still have my door cracked open a few inches until i can afford a 250cfm exhaust fan. i dont think im getting the hot air out fast enough with the small exhaust fan that i have.