Still in first grow, climate control challenges

[ms48130]

Sometimes we are just at the mercy of mother nature and ambient conditions. Thinking about it, don't apples, oranges, etc all live through changing climates during their fruit times? 40 years ago, some of used that to sow cannabis among corn...and it got what the corn got, and we grew truckloads of weed.
Now we try to convert all that natural stuff to how WE want it to be and its no surprise we have multiple issues along the way that may harm our luscious fruit. Getting our systems as close to "natural" was my goal. I use inkbird controls to exchange my air....bringing in outside air and ambient conditions...Supply light energy and timely nutrition, you're just waiting on the fruit to ripen.
Heat is the most common problem to tent grows and we all fight it from time to time. The best change I made the past few runs during summer was addition of a dehumidifier/ac unit. A little rigging for the exhaust and installing a port in the flowering tent was easy. Being an old engineer type, I know to assess, assess, assess before change, then assess, assess some more. Patience is the key.
With that the only change in 6-8 months, I noticed significant changes in every plant, most I've grown previously and knew what to expect.
Yeild, firmness of the bud and frostiness all have increased...To collate that with our southern USA high humidity, controlling humidity in flower is essential to all other aspects. I'm just fortunate to have separate veg and flower areas.
I'd add a unit...set up properly gives a different type of control that DOES make a difference.

being my first grow, I'm just looking for guidance - your input is appreciated.

Do you have a dehumidifier w humidistat, or a humidity controller like the Inkbord?

 

[automan2]

Yes, my fans are controlled by inkbird controls which only manages temps but I manually control the dehumidifier since turning on and off like the fans is not conducive to working long. Everything is automatic except feeding...and being home 24/7 makes it easy.
AFN is a good place for friendly supportive information and less picking pepper out of fly shit.
Any advice you need, holler. There's a lot of simple growers with simple techniques that helps keep it simple.

 

[Simplicio]

I use humidifiers during flower in hydro to keep humidity in the 60s, in order to follow the unmodified VPD chart.
I don't top or train, which leads to super-dense vegetation, and buds top to bottom.
Even with these conditions I've never had bud rot.
But I do have good air flow in/out and good circulation inside.

 

[ms48130]

I bought one of the Eva-Dry E-500 (dessicant) dehumidifiers, and it maxed out on the first night of use .

There's really little room in the tent for a dehumidifier, and I'm _thinking_ that putting a dehumidifier OUTSIDE the tent may be at least as useful, if not more so, than having a dehumidifier INSIDE the tent, since the air exchange is simply going to continue to suck in humid air from outside the tent. This would also allow for getting a dehumidifier that would be appreciably larger than a small one inside the tent (although I'd try to continue to use the Eva-Dry inside the tent).

Agree/make sense, or challenge & suggest alternative?

 

[Simplicio]

Exhaust fans are much cheaper to run than dehumidifiers.
A 6 inch fan will probably solve your problem.
I have a couple 2 x 4 ft tents, and a 4 inch isn't quite powerful enough.

You might also consider using both 4 inch fans as exhaust fans, because an intake fan will be able to move more air as used an exhaust fan.
As a first try you might hook them in series in the same exhaust duct.
If that doesn't work, giving each its own duct by hooking them in parallel should.

For our purposes, air is an incompressible fluid, and what gets exhausted by a fan must also have been sucked in by that fan, so an intake fan isn't necessary unless the exhaust fan needs help.

 

[MI_sterGreen]

My first grow is moving along fairly well. I'm in my 2nd week of flowering on 2 (auto) plants, pre-flower on 1 (also auto), and still in veg on the 4th (photoperiod, working through manifolding). My light schedule is still 20/4 for the time being.

My temps are running about 85F on average with ~60% RH. I have no ability to add A/C to this small (2x2.5x5) tent. I do have a 4" intake fan and a 4" exhaust fan, both running 24/7.

Today, I removed my humidifier as it was on the lowest setting, and since 2 plants are in flower I thought it better to dry the space a bit. I do have 3 fans (1 tower and 2 clip fans) running 24/7 as well.

At this point I'm a bit conflicted on how I'll be able to improve the temp & humidity. Higher volume intake & exhaust? Dehumidifier?

Open to all input but again, adding an A/C unit is out of the realm of possibility.

Thanks in advance!

Where is the tent exhausting to? If you're not exhausting the air outside of the closet the tent is in, you're basically just pulling in the same temp air as going out. You want to have the intake pulling cool fresh air in and exhausting the warm air out

 

[ms48130]

Exhaust fans are much cheaper to run than dehumidifiers.
A 6 inch fan will probably solve your problem.
I have a couple 2 x 4 ft tents, and a 4 inch isn't quite powerful enough.

You might also consider using both 4 inch fans as exhaust fans, because an intake fan will be able to move more air as used an exhaust fan.
As a first try you might hook them in series in the same exhaust duct.
If that doesn't work, giving each its own duct by hooking them in parallel should.

For our purposes, air is an incompressible fluid, and what gets exhausted by a fan must also have been sucked in by that fan, so an intake fan isn't necessary unless the exhaust fan needs help.

My tent is 2'x2.5'x5', so around 1/2 of yours. My question to you regarding a larger exhaust fan is, do you think that the fan alone reduce RH lower than the RH outside the tent?

I'm going to need another fan anyway for a drying tent which I think I'll put the 4" fan into, so a 6" fan is certainly a consideration!

 

[ms48130]

Where is the tent exhausting to? If you're not exhausting the air outside of the closet the tent is in, you're basically just pulling in the same temp air as going out. You want to have the intake pulling cool fresh air in and exhausting the warm air out

My exhaust right now is (filter then 4" fan inside of tent) exhausting out top of tent thru 4" duct. Also have a 4" intake fan at the bottom of the tent. The tent is in a walk-in closet, so the air outside the tent is only marginally cooler (~5*F) than the air inside the tent. The RH outside the tent is about 10% lower than inside the tent.

 

[Simplicio]

My tent is 2'x2.5'x5', so around 1/2 of yours. My question to you regarding a larger exhaust fan is, do you think that the fan alone reduce RH lower than the RH outside the tent?

I'm going to need another fan anyway for a drying tent which I think I'll put the 4" fan into, so a 6" fan is certainly a consideration!

Oops, eyesight thought you had 2 x 4.
The 4 inch should be big enough, and 2 should be more than enough.
With very fast exhaust fan speed, the conditions inside the tent can come close to those just outside the tent.
During lights on, the heat from the light would then reduce the humidity below what it is outside the tent.
During lights off, without the light to reduce humidity inside the tent, it will be close to the humidity outside the tent.

 

[ms48130]

Oops, eyesight thought you had 2 x 4.
The 4 inch should be big enough, and 2 should be more than enough.
With very fast exhaust fan speed, the conditions inside the tent can come close to those just outside the tent.
During lights on, the heat from the light would then reduce the humidity below what it is outside the tent.
During lights off, without the light to reduce humidity inside the tent, it will be close to the humidity outside the tent.

So I bought a new AC Infinity 6" fan & filter tonight, and I'll relegate the 4" to a drying tent (when they're ready!). Also found a dehumidifier beg enough for the closet so I'll lower the closet's RH as well, and the big fan will help the inside tent air.