RH for flower need help

[Wzrdovoddz]

Hey everyone ,

Any ideas on what the ideal RH for flower should be when lights on and lights off? I am using two 1200w led grow lights and today is my first day of flower And this is my first grow. I’m pretty excited and trying to make sure my environment is dialled in. I am growing in Promix HP with micorhize in 7 gallon pots. Any help would be great. Thanks in advanced.

 

[xtraLRG420]

Whether the lights are on or off your RH in early flower should be about 45%. As buds develop you wanna start dialing that back a little just to where you aren't developing any mold.

 

[Wzrdovoddz]

Ok sounds good. Thanks for the quick response

 

[Wzrdovoddz]

Whether the lights are on or off your RH in early flower should be about 45%. As buds develop you wanna start dialing that back a little just to where you aren't developing any mold.

Any idea how to set humidity on toshiba 30 pint dehumidifier?

 

[Nrk.cdn]

First..put a hydrometer in there and start tweaking unit..if the unit has no RH display.

 

[Hot Diggity Sog]

I know these humidity levels look a little scary, but once I began sticking to this chart, I never looked back.
This is called Vapor Pressure Deficit

 

[Wzrdovoddz]

I know these humidity levels look a little scary, but once I began sticking to this chart, I never looked back.
This is called Vapor Pressure Deficit

View attachment 4465621

Is that the Vpd for flower ?

 

[dubekoms]

I know these humidity levels look a little scary, but once I began sticking to this chart, I never looked back.
This is called Vapor Pressure Deficit

View attachment 4465621

Do you ever get mold? My temps are at 82 with led and I know I would get mold at 80 rh later in flowering.

 

[Hot Diggity Sog]

These humidity levels are for everything...seedlings, veg and flower. That said, my temps never exceed 78 and are typically in the low 70's. I too would never let the RH sit above 70. Good air flow and air exchange are always important (obviously).

 

[Wzrdovoddz]

This should help

 

[Wzrdovoddz]

These humidity levels are for everything...seedlings, veg and flower. That said, my temps never exceed 78 and are typically in the low 70's. I too would never let the RH sit above 70. Good air flow and air exchange are always important (obviously).

I posted Vpd chart for different stages

 

[Hot Diggity Sog]

I posted Vpd chart for different stages

Interesting.

 

[fragileassassin]

This should help

That chart is pretty much what I do.
80F 60%+ from start to flip, turn my fan up a bit after flip then bring it down to 40% once buds start bulking up.
I cant really get it any higher than 60%or id shoot for 65%

 

[Wzrdovoddz]

That chart is pretty much what I do.
80F 60%+ from start to flip, turn my fan up a bit after flip then bring it down to 40% once buds start bulking up.
I cant really get it any higher than 60%or id shoot for 65%

Nice good to know. I got the dehum dialled in right now at 65%

 

[Nefrella]

View attachment 4465877

This should help

Awesome brother, thx! Looks like its time to purchase a dehumidifier

 

[Nefrella]

Awesome brother, thx! Looks like its time to purchase a dehumidifier

Anyone used this one, or have a suggestion for a good mid priced dehumidifier?

Check this out at Amazon.com
hOmeLabs 1,500 Sq. Ft Energy Star Dehumidifier for Medium to Large Rooms and Basements - Efficiently Removes Unwanted Moisture https://www.amazon.com/dp/B073V9MG3Y/ref=cm_sw_r_other_apa_i_L3cUEbKV5T1DY

 

[Dontjudgeme]

I typically stay at 50% RH through my whole flower. Last 2 weeks I drop it 40%. High humidity really isn’t an issue as long as there’s sufficient air flow and exchange. Stagnant air is where the mold comes from. I’m sure I could get away with higher humidity levels, but I’ve never had an issue staying at 50. If it ain’t broke, don’t wanna fix it.

 

[Nefrella]

I typically stay at 50% RH through my whole flower. Last 2 weeks I drop it 40%. High humidity really isn’t an issue as long as there’s sufficient air flow and exchange. Stagnant air is where the mold comes from. I’m sure I could get away with higher humidity levels, but I’ve never had an issue staying at 50. If it ain’t broke, don’t wanna fix it.

Copy. I have adequate airflow, so guess I'm gonna stop trippin'

 

[GBAUTO]

Anyone used this one, or have a suggestion for a good mid priced dehumidifier?

Check this out at Amazon.com
hOmeLabs 1,500 Sq. Ft Energy Star Dehumidifier for Medium to Large Rooms and Basements - Efficiently Removes Unwanted Moisture https://www.amazon.com/dp/B073V9MG3Y/ref=cm_sw_r_other_apa_i_L3cUEbKV5T1DY

How large is the room your grow is in?
I run a Frigidaire 50pt dehuey in my upstairs grow room(450 ft3), and it will completely fill every day(I live in the Smokies).

 

[Nefrella]

How large is the room your grow is in?
I run a Frigidaire 50pt dehuey in my upstairs grow room(450 ft3), and it will completely fill every day(I live in the Smokies).

~300 sq. ft. Room size that the tent is in. RH is around 55% in the flower tent, and I'm exhausting outside 24/7. Do I really need a dehumidifier?