Need help dialing in RH in 2'x4' grow tent. mini dehumidifier did nothing

Long time shmoker 1st time grower. Just flipped my 2 Amnesia Fast girls to flower. Been going well so far. In S california so generally high humidity not an issue (although moving to midwest in 5 months so this thread will help more when I move). Of course the week I wanted to start flower (end Dec.) we hit several days in a row of rainy weather with high humidty. Bought a mini dehumidifier (eva-dry 1100) plopped it in tent right in front of intake and maybe got the rh to drop 2% over 2 days of trial. All week I’m @ 60% RH w lights on (avg temp 78F) & 70% RH lights off (avg temp 67F). Tent seems to stay @ 10% higher RH then house RH. Mars hydro tsl2000 light, 4" inline fan exhausting into attic, passive air intake 6" secret Jardin light baffle insert. clip fan circulating air low w small osscalating fan blowing across tops of ladies. Coco/perlite “tupar” medium in 3gallon fab pots, was doing twice a day high water fertigation watering method but cut that back to once a day to see if that helps RH at all (always watering to runoff & removing saucer water daily) Thanx in advance for any advice

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Hy @JimmyDuxFan and welcomed to the community if all you plants are in flowering stage I deal with my hr without humidifier just opening my tent

For example if I closed my tent the hr go from 60% to 85%

And opening my tent the hr go from 55% until 40% sometimes little low but all time be in 45%

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Actually you’re sitting pretty for daytime temp and humidity. The night time temp and humidity are an issue though. At 67° you want to be around 40-50%. Any way of getting a larger humidifier or maybe a heat source to bring the temps up?

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welcome to the community and the humidity. These pros will help you.

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Is your 4” fan causing negative pressure (sucking in the sides of the tent)?

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My tent is in corner of my large master bedroom so I would’t be able to open tent during “lights out” because the rooms being used (main reason I added the Light baffle air intake and sealed up the tents vents)> a small heater could be an option but space is tight in the 2’x4’, I might have to try putting a heater right next to air intake on outside of tent. Gonna return this $40 dehumidifier and look at small space heaters. My RH #'s will prolly be fine most of flowering time as this higher humidity is rare in Ca in winter but I’m kind of a perfectionist and want to make it close to perfect I can. In midwest I know I’ll deal w this situation more often but I’ll be in a basement then and prolly will do large couple hundred $ room dehumidifer then.

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As for neg pressure yes some sucking in when I crank inline all the way up. The light baffle does restrict air flow alittle more the just having 1 the bottom tent flaps open but there is a definite difference in temps and rh by adjusting inline fan speed up and down. Was running it maybe half speed through veg as temps aren’t a prob w led’s but have cranked it to max when Rh grew this week and thats when I could see some neg pressure wall sucking in.

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@JimmyDuxFan
My tent is a 2x2x4 to but I had my tent in the living room open like this
IMG_20211230_185851

Went hr is to low I jut cover with tower and hr get up like 10% or 20% up

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50% is good to run until harvest just look you plants, you should be good high hr make mold on you plants

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I added a small space heater outside the tent next to the intake and lights out I’m now keeping it @ 76F and the rh has been @ 60%avg lights out now. Gotten it down to 48-49% rh couple lights out even. Humidty has been all over the place in S Ca. last 3 weeks. Pay attention and adjust I guess lol

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