Set up issue and humidity

Some people have their dark period during the hottest part of the day.

I grew tired of putting things on my tents' floors, where they get in the way.
Now I use plant hangers suspended from my basement ceiling, put heaters/humidifiers on them, and blow into the tent thru an upper port hole, above the plants.
I also have tall wire shelving units beside the tents to put things on. These work even better.
 
@Mooregrow welcome to the forum :welcome::pass:
@St. Tom thanks for the tag :bighug:

I'll try and look at as many contributing factors as I can, some solutions may cost some money, some may not.

If you have to fork out some cash, look at it as an investment. Once an issue has been addressed, it should last for years.

I will add a synopsis at the end for quick and convenient info.


Standing water will evaporate in a warm tent. I use a wet/dry vacuum to suck up my run off! It is quick and easy.

I had a quick look and in the US you can pick one up from around $70. Maybe even cheaper if you have a look around, I don't live in the USA.

In the UK I picked one up for £44 for my wet/dry vac (I wouldn't be without it with Drain To Waste (DTW) in coco)

Do you know what the RH is outside of the tent? I live in a high RH area so RH is relatively high for me compared with people who leave in the east of my country.If you have high RH outside the tent, you could run a dehumidifier to dehumidify the air before it goes in the tent.

Reducing the temp - if this is possible, it will help, as hot air holds more moisture than cool air.

Insulating the tent in cold weather is also a good idea.
A thermostatic tube heater is a good way to keep temps at an ideal heat in winter but if your not getting enough heat, then your heater isn't big enough.

You may find the heater you have is sufficient once tent is insulated. If you still can;t keep the heat up after insulating, you will need to add another tube heater. Luckily they don't take up much space.

Lollypopping your plants will allow more air to circulate below the canopy.
Any foliage low down, that doesn't get decent light penetration, can be removed.
It is waste of time letting the larf/popcorn buds grow.

You can use clay pebbles as a mulch on the surface of your substrate, to stop excessive moisture loss from you pots.
However I think you humidity problems is fro the plans transpiring.

Synopsis

In hot weather


Reduce the number of plants in the tent - less plants equals less transpiration and gives more space for air to move around your tent
We all want to grow as many plants as we can but pushing the limits of your grow space can lead to problems.

Reduce heat- less moisture held in the air and plants transpire less moisture.

Dehumidify air going into tent - take out moisture before it goes in the tent.

Clay pebble mulch - stops evaporation from the top of your pots.

Possibly change from fabric pots to solid pots - less moist surface area on the sides of the pots from which moisture can evaporate.

Remove standing water, with a wet/dry vac - in a hot tent the standing water will evaporate creating a higher RH.

Have a wet/dry, water/feed cycle - cannabis likes a wet/dry cycle and you will also reduce the amount of times you need to water.
A wet/dry cycle allows the ph to fluctuate a little giving better nutrient take up and allowing more air to the roots.

Remove unnecessary foliage low down on the plant - by lollypopping, helps, air flow and there is less foliage to transpire moisture.


In cold weather

Insulate tent- The tube heater you have, may then be right size and provide enough heat.
Polyisocyanurate (PIR) insulation board is relatively cheap, I believe Cellotex is available in the USA

If heat still isn't enough- add another tube heater (thermostatic controlled)

I hope that helps answer your questions

Have a great day and an even better grow
:pass:

Arty
 
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Yeah I’ve done that. Well In Rockwool, I think it’s more of the air exchange and I have negative pressure it’s not holding any heat.

Moved my meter up so it was of the ground and put it around the height of the top of the plants and I have 80% humidity I literally don’t get it
 
@Mooregrow welcome to the forum :welcome::pass:
@St. Tom thanks for the tag :bighug:

I'll try and look at as many contributing factors as I can, some solutions may cost some money, some may not.

If you have to fork out some cash, look at it as an investment. Once an issue has been addressed, it should last for years.

I will add a synopsis at the end for quick and convenient info.


Standing water will evaporate in a warm tent. I use a wet/dry vacuum to suck up my run off! It is quick and easy.

I had a quick look and in the US you can pick one up from around $70. Maybe even cheaper if you have a look around, I don't live in the USA.

In the UK I picked one up for £44 for my wet/dry vac (I wouldn't be without it with Drain To Waste (DTW) in coco)

Do you know what the RH is outside of the tent? I live in a high RH area so RH is relatively high for me compared with people who leave in the east of my country.If you have high RH outside the tent, you could run a dehumidifier to dehumidify the air before it goes in the tent.

Reducing the temp - if this is possible, it will help, as hot air holds more moisture than cool air.

Insulating the tent in cold weather is also a good idea.
A thermostatic tube heater is a good way to keep temps at an ideal heat in winter but if your not getting enough heat, then your heater isn't big enough.

You may find the heater you have is sufficient once tent is insulated. If you still can;t keep the heat up after insulating, you will need to add another tube heater. Luckily they don't take up much space.

Lollypopping your plants will allow more air to circulate below the canopy.
Any foliage low down, that doesn't get decent light penetration, can be removed.
It is waste of time letting the larf/popcorn buds grow.

You can use clay pebbles as a mulch on the surface of your substrate, to stop excessive moisture loss from you pots.
However I think you humidity problems is fro the plans transpiring.

Synopsis

In hot weather


Reduce the number of plants in the tent - less plants equals less transpiration and gives more space for air to move around your tent
We all want to grow as many plants as we can but pushing the limits of your grow space can lead to problems.

Reduce heat- less moisture held in the air and plants transpire less moisture.

Dehumidify air going into tent - take out moisture before it goes in the tent.

Clay pebble mulch - stops evaporation from the top of your pots.

Possibly change from fabric pots to solid pots - less moist surface area on the sides of the pots from which moisture can evaporate.

Remove standing water, with a wet/dry vac - in a hot tent the standing water will evaporate creating a higher RH.

Have a wet/dry, water/feed cycle - cannabis likes a wet/dry cycle and you will also reduce the amount of times you need to water.
A wet/dry cycle allows the ph to fluctuate a little giving better nutrient take up and allowing more air to the roots.

Remove unnecessary foliage low down on the plant - by lollypopping, helps, air flow and there is less foliage to transpire moisture.


In cold weather

Insulate tent- The tube heater you have, may then be right size and provide enough heat.
Polyisocyanurate (PIR) insulation board is relatively cheap, I believe Cellotex is available in the USA

If heat still isn't enough- add another tube heater (thermostatic controlled)

I hope that helps answer your questions

Have a great day and an even better grow
:pass:

Arty
Thanks I lot, I will try some things out like you have said and see what happens. I think I will try a dehumidifier outside the tent like you said and see how that goes that’s a good idea! And another tube heater I think the one I have is only like 40w I think the bigger ones are 80 but there like three ft.
Thanks for all the info everyone it’s helped hopefully I figure it out and get a stable environment
 
Thanks I lot, I will try some things out like you have said and see what happens. I think I will try a dehumidifier outside the tent like you said and see how that goes that’s a good idea! And another tube heater I think the one I have is only like 40w I think the bigger ones are 80 but there like three ft.
Thanks for all the info everyone it’s helped hopefully I figure it o
Tube heaters can get too long for a tent if you upsize, I suggest using 2 smaller ones. It is also cheaper that way as you already have one small one.
 
Thanks I lot, I will try some things out like you have said and see what happens. I think I will try a dehumidifier outside the tent like you said and see how that goes that’s a good idea! And another tube heater I think the one I have is only like 40w I think the bigger ones are 80 but there like three ft.
Thanks for all the info everyone it’s helped hopefully I figure it out and get a stable environment

Go back in time - use HPS and/or Metal Halide Lights - I had an LED light and in my controlled room it worked fine but when I expanded into a second tent I had to setup in another section of basement - I tried a heater but the temps would get outa wack, room was too large and open, so I decided to go back to HPS light for the flowering phase and it worked like a charm - tent temps stayed in 76 degree range ..... Why invest in heat when the ballast can do the work and it was cheaper on electric too!
 
Hi pal least you have a few options here i hope you fiquire it out one way or another . thats a tube heater i use when needed it takes hardly and floor space and as arty said maybe get 2 shorter ones
 

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Right... so I though fuck it let’s give it a try so I pulled out some insulated ducting and put a vent cover in one of the cupboard we just have coats ect in there. It’s a bit of a long way though and my negative pressure has obviously increased I have a single speed rhino pro fan and no intake fan. The tent walls are pulling in more so I’m not worried I mite have to much negative pressure .... but... humidity and temps sorting itself out. I will find out tonight if it’s going to keep it warm enough or not so let’s see
 

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I’m worried I mite have no much negative pressure*
That is a long length of ducting, you will probably need an inline ducting fan to help out the extraction fan.
It is always easier to suck than blow & with long lengths of ducting, any air your trying to move, gets harder to do so, the longer the length of ducting you have.
If tent wall sucking in then too much extraction, not enough intake.
With passive intake you need 4 x the hole diameter than the vented out via fan, for most people that is too much hole.
Best use a slightly less powerful intake fan to bring in fresh air (or use a fan speed controller) so you still have negative pressure but not so much that the walls get sucked in.

@St. Tom Thought you might like this post , I think you may have skipped past it https://www.autoflower.org/threads/set-up-issue-and-humidity.77447/page-2#post-2275176
 
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