Why does my humidity spike at lights out?

good stuff

cobshopgrow said:

interessting read, never thought about that plants in coco drink that much more.
More RO water would be probably easy to make while not a solution at all like it sounds.
Isnt a 500gdp filter a direct drop in for the 350? just new 500gdp membrane needed.

Hope you get it under control, humidity is really difficult to deal with.
You wrote probably somewhere, but may i ask whats your outside RH and temp in colorado?

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Mine uses an Axion 500 GPD membrane already. Temp varies, RH% is often around 19% in the summer, winter it could be 60% but 20F so thats basically no water in the air. It's dry as fuck here.

Renfro said:

Mine uses an Axion 500 GPD membrane already. Temp varies, RH% is often around 19% in the summer, winter it could be 60% but 20F so thats basically no water in the air. It's dry as fuck here.

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Yep .... i battle rh 3/4s of the year with a dehuey, i spend the other 1/4 battling it with humidifiers lol

As soon as i start running my pellet stove, rh in my house drops drastically ofcourse.

"dry as fuck" hit the nail.
You really deal with some massive evaporation there wow.

i have problems keeping the rh down in summer and up in winter, later is easier to deal with, there is maybe a time in between the seasons where it would be perfect.
Pretty much the other way arround,lol.

im probably not going to be growing during the summer have way to many problems with humidity and heat

Renfro said:

This chart illustrates the humidity spike phenomenon in one of my flowering rooms.

View attachment 4431983

The lights go off at 3:45 AM, you can see the humidity rising despite the vent cycle bringing in fresh cold and very dry air. If not for that vent cycle and dry air my dehumidifiers wouldn't stand a chance of keeping up and the humidity climbs into the upper 50's. You can see that during the lights off period, the dehumidifiers in that room are struggling to maintain the RH% and the room temp climbs from 75 to 80 and the blower kicks in really helping the RH% situation. You can see the RH% drop a little bit when the temp drops during the dark, without that it would just climb and level out in the upper 50's about 7 or 8 hours after lights out. I only have it vent down to 75 because the colder the air is the less effective the dehumidifiers are.

It's a real balancing act and

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Ill show you my set-up when i get home. I used to think the De-Hu was the answer n almost spent a $G on a Quest too.
I understand the difference in our room sizes & Bio-Mass. You dont loli-pop much do to the sidelighting it looks from pics so your plants have extreme Mass. Considered some hair cut down there? Would make a big difference in humidity. That is not a determining factor as to whether this works for you as it did me, i doubt but would help.
Ive been able to eliminate the big full time Scrubber too. Get no complaints.
So every 1,1/2 hrs the intake & scrubber connected exhaust (which is up high where heat & humidity go) kicks on for 1/2 hr. both the same size 6" (you could do x2, 8") inlines. This keeps the room semi-equalized as the negative air pressure when only using an exhaust in a sealed room is not a happy place for the girls.
The intake is an 8" hole with a 6" fan, low to the ground, intaking the lowest point of heat & humidity through filters. So depending on season temp & regular, big, HomeDepot De-Hu on the side of the room that is not a grow. This maintains proper humidity levels throughout as well as veg.
The room Has another equal Reg, self pumping Du-Hu ($160) in the grow set to 50% allowing 62ish% during flower. In Pro-Mix.
Lights out, 1 hr exhaust & intake kick on for 1 hr starting 15 min before lights out. That handles that. Same thing but only 1/2 hr at lights on. Adjusting the Co2 to shut of during ehaust times at lights on. Twice should work for you, i do once during lights on at tge 1/2 way point.
Idk! Intake & exhaust have reduced my du-hu needs, regulated temps & humidity at the crucial, hard to do w/o heat emitting de-hu's that often fight the AC.
Now i have a precipitation thermostat that kicks fans on @ my desired setting instead of timers. $28 for that thing.
Ok, rambillidous over n out!
Nice farkin Grow Man!

hybridway2 said:

Considered some hair cut down there? Would make a big difference in humidity.

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Oh they got that and massive defoliation this round.

Was hard to understand your post. Honestly I gave up lol. I know it's hard to post from a phone.

For me the difference maker was coco. That changed the whole equation.

Renfro said:

Oh they got that and massive defoliation this round.

Was hard to understand your post. Honestly I gave up lol. I know it's hard to post from a phone.

For me the difference maker was coco. That changed the whole equation.

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Damn, i know it sux writing from phone.
I get it. Big plants suck that CoCo dry quickly. Multi-feeding. Either way, even better you have a fancy tool that measures & records data.
Uhm, will send pic later but basically controlled air in & air out (through a scrubber) set on a timer or by using a humidity detecting device that turns the fans on. In & out at same time to equalize pressure & replace moist air .
Has leveled out my room w/o such a need for a real De-Hu.
Just x2 regular, self pumpers from the Depot. One in the room & one in the adjacent room/area keeping intake @ 40-50%ish & i keep the i take low to the floor.
I abbreviate & even occasionally make up my own words. Lol! But the worst is when I'm mad dabbed out like when i wrote that. Dabby doo!
You're not the first to not understand my post. No biggie, just trying to help.

Seen the thread and thought you were actually asking that question lmao

Brettman said:

Seen the thread and thought you were actually asking that question lmao

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Renfro said:

lol, I figured that title would be good for those using the search feature.

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