Very High Humidity

[Paddie]

Hi All. New here. First grow. Having issues lowering my humidity. Would appreciate some experienced help.

Whole setup below is in basement which is always cold, typically between 17 and 21 degrees Celcius. Intake draws from the floor outside space and exhaust exhausts outside space at ceiling.

Setup: 3 x 3 x 6 grow tent, 1 x 4" 103 cfm intake, 2 x 4" 235 cfm exhausts running full tilt, 600 W Viparspectra LED @ 12/12, 2 x oscillating fans, 1 high, 1 low and a 250 cubic foot dehumidifier inside tent on 24/7.

Strains: 1 x Seedsman, Auto Amnesia; 1 x Garden of Green, Super Critical CBD Bud.

Grow Medium: Coco Coir, 3 Gallon Smart Pots.

Training Methods: Auto: LST only; Photo: Mainlined. Both defoliated when required.

Watering method: Drain to waste.

Both plants doing very well.

Problem:

Cannot get HR% below 54% during the day with LED on. With LED is out, HR% climbs to 59%

Dehumidifier is drawing out 1/4 gallon of water a day. Air flow is not an issue. Negative pressure in tent is solid.

Getting a more powerful dehumidifier isn't in the cards right now, nor is getting an A/C. I'm worried about White Powder Mold and Bud Rot at the HR%'s.

What can I do that i haven't already?

Go.

 

[Nunyabiz]

Well you just nixed the only two possible solution to actually lower the humidity.
Bigger dehumidifier and AC.

But fortunately as long as it stays mostly below 55% and you keep lots of airflow going you're OK.
In bud you just dont want your humidity over 65% especially in the last couple weeks of bud.
Try to keep them trimmed of excess leaves to keep airflow through the plant and less contact of a leaf laying on another leaf.

Bit late for this grow but foliar feeding all through veg with silica will help stave off powdery mildew

 

[Weaselcracker]

Your humidity is basically perfect as is. No need to get it any lower.

 

[LiberalThinker]

Hi All. New here. First grow. Having issues lowering my humidity. Would appreciate some experienced help.

Whole setup below is in basement which is always cold, typically between 17 and 21 degrees Celcius. Intake draws from the floor outside space and exhaust exhausts outside space at ceiling.

Setup: 3 x 3 x 6 grow tent, 1 x 4" 103 cfm intake, 2 x 4" 235 cfm exhausts running full tilt, 600 W Viparspectra LED @ 12/12, 2 x oscillating fans, 1 high, 1 low and a 250 cubic foot dehumidifier inside tent on 24/7.

Strains: 1 x Seedsman, Auto Amnesia; 1 x Garden of Green, Super Critical CBD Bud.

Grow Medium: Coco Coir, 3 Gallon Smart Pots.

Training Methods: Auto: LST only; Photo: Mainlined. Both defoliated when required.

Watering method: Drain to waste.

Both plants doing very well.

Problem:

Cannot get HR% below 54% during the day with LED on. With LED is out, HR% climbs to 59%

Dehumidifier is drawing out 1/4 gallon of water a day. Air flow is not an issue. Negative pressure in tent is solid.

Getting a more powerful dehumidifier isn't in the cards right now, nor is getting an A/C. I'm worried about White Powder Mold and Bud Rot at the HR%'s.

What can I do that i haven't already?

Go.

Perfect then after your lights are on.

 

[Weaselcracker]

Just make sure you have good air movement with desk/floor fans on 25/7. I’ve rarely had RH below 60 in years - much of the time much higher.

 

[Paddie]

Thanks for the input. I guess I'll have to play it out and hope for the best. Appreciate your time.

 

[Blew Hiller]

54% is fine....I was battling getting it below 75% all winter in a damp basement and they did fine....

group 4x4

• Blew Hiller
• Feb 7, 2019

Blew Hiller Winter Grow 2019

 

[PE636]

You're not in terrible shape. What do you see for temps after a few hours of lights on?

 

[No Pain]

Your humidity is basically perfect as is. No need to get it any lower.

as stated for this stage your rh is pretty much perfect ….before you start pulling your hair out and loosing sleep check out this vpd chart ...if you follow this you will have great results .. VPD is the Place to be ! now you may have to go get a laser thermometer to check your lst ( leaf surface temps) and input it .

 

[Paddie]

Lights off 19 C, lights on 21.5 C. Heater is turned off at this time.

 

[bobrown14]

RH is perfect temps are perfect

Go take a walk and reflect on you success. You will be fine.

 

[Paddie]

Thanks all. Appreciate your help. I'll keep you posted. Cheers.

 

[Paddie]

Update: Flowering nicely. Budding up nice and thick. Two more weeks on the auto, four on photo before flush.

 

[bobrown14]

Flush??

You sure you need to flush CoCo??

Why not just plain water and just double the amount till harvest?

 

[Paddie]

That's what I meant by flush. Straight water for ten days @ 50% runoff. Should have clarified. Cheers.

 

[bobrown14]

water for the win

 

[Paddie]

Just an update, left to right: Auto Amnesia, 4 weeks to flush, 14"; Photo Super Critical CBD Bud, 5 weeks from flush, shy of 3'.

Edit: in 3 Gal pots.

 

[Nunyabiz]

Looks good

 

[Paddie]

Just an update. They are coming along nicely.