Humidity at dark

1000w 8x8 room, 9000btu LG a/c portable.

The a/c never cuts off, when it hits the set temp the compressor turns off but the fan keeps running.

At night, the a/c fan running constantly, which puts the humidity up to ~70%. Running autos so only 4hrs off "dark time", so the high humidity is short lived...

I've never had mold before, but this is my first cycle with the a/c...


My question is: With great circulation does the 70% humidity (for about 4hrs) significantly increase my risk for rot and mold(s)??? They're all just starting to flower now.

yes. lights off is when rh spikes. you need a dehumidifier.

or setup additional extraction fan to run at night only?

I can't give up the a/c, it's letting me keep a 1000w 20in away... I used to have to keep a 600w 36in away...

Unless you develop actual mold I wouldn't worry about that short of a time period. The fan moving air will suffice and save your money on the dehumid for now. 4 hours? I would add a second fan before the cost of a dehumidifier and the heat those damned things generate.

At least autos dont have a long flower period so the risk of mould getting to the buds is lessened. I would still be wary of that level of night humidity though, that said I have had nights of over 80% with photoperiods and still didnt get any bud rot - just a little powdery mildew, and thats 12hrs dark obviously.

I find my autos love a dryer medium so I dont fully soak the pots with every watering, and this I think makes a slight differnece in night time humidity.

my belief anything above 60 is doin more harm than good not only are you at risk for mold but also slow plant growth 4 hours or 1 uneeded stress that can be avoided should be

The last week in my region we have seen 100% humidity levels. I have a great air circulation system ,but cannot afford a dehumidfier. When the light is on the temps are 72-77 F and RH is 47-54%. When the lights are off the temps are around 65-70F and RH with highs over 80%. I know that these high levels of humidity are only for a few hours, but it worries me. I have 2 oscillating fans going all the time as well as almost 1000 cfm total exhaust going 24/7. I haven't seen any mold or negative signs, and I believe we are due a humidity relief soon. As long as your plants stay healthy I would not worry.

run a small ceramic heater during the 4 off, to maintain air temp. it'll up your bill, but it should also prevent that swing in rh

scroglodyte said:

run a small ceramic heater during the 4 off, to maintain air temp. it'll up your bill, but it should also prevent that swing in rh

Click to expand...

i don't care about power cost, it's a relatively low cost if you think about it. This option sounds like the right choice for me, ceramic heaters are way cheap.

Thank you.

All depends on the size and wieght of the colas. Also you need 50w per sq/ft ,atm you have about 15.

Too bad you can not get the ac to run at night and help pull moisture from the air.
You mentioned that cost was not an issue. Here is a link that may help.
http://www.greenbuildingadvisor.com/blogs/dept/energy-solutions/removing-moisture-homes-air-conditioners

*BUDS said:

All depends on the size and wieght of the colas. Also you need 50w per sq/ft ,atm you have about 15.

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I only use about a 3x3 or 4x4. 7 autos and 2 photos.

charface said:

Too bad you can not get the ac to run at night and help pull moisture from the air.
You mentioned that cost was not an issue. Here is a link that may help.
http://www.greenbuildingadvisor.com/blogs/dept/energy-solutions/removing-moisture-homes-air-conditioners

Click to expand...

I mean, I guess I could set it at like 60, it would never make it that low so it would run 24/7, but then my plants would be too cold all day.

Buds, you answered a bunch of my dumb questions ~year ago when I was starting out. Good to see you again, and thanks.