Need help raising relative humidity in a larger room

[stoned-monkey]

Homebrewers use co2 also.
I think what lightgreen was talking about when mention the graph is to make sure its specifically for cannabis.
Yes mold is a very real threat. There are treatments for it but best not to get it in the first place.
Co2 is used to maximize yeild, but EVERYTHING else needs to be dialed in, temps, rh, nutes, containers, grow method, etc.
Think of it like this, protein is needed to build muscle, but drinking all the protien shakes without a solid workout routine wont give you more muscles, just a lighter wallet.

 

[GroErr]

Yeah seeing a lot of references to that vpd chart. While it may technically be the most efficient ranges for growth, they are not practical indoor and all you're doing is setting up for mould and PM issues. I've seen PM take at anything over 55% so that's my max and what I have my dehuey set for during lights off. Regardless of what some chart says, it would probably be fine outdoor, much like our weather here in summer, but not indoor.

Here's the chart btw, in this one the brown/gold areas are the supposedly ideal ranges:

 

[NugHeuser]

Homebrewers use co2 also.
I think what lightgreen was talking about when mention the graph is to make sure its specifically for cannabis.
Yes mold is a very real threat. There are treatments for it but best not to get it in the first place.
Co2 is used to maximize yeild, but EVERYTHING else needs to be dialed in, temps, rh, nutes, containers, grow method, etc.
Think of it like this, protein is needed to build muscle, but drinking all the protien shakes without a solid workout routine wont give you more muscles, just a lighter wallet.

Awesome analogy man, makes perfect sense. And yeah I'll look a little further into all these vpd charts, they are all over Google images but I didn't realize that vpd could be different for different types of plants. Great info.

 

[NugHeuser]

Yeah seeing a lot of references to that vpd chart. While it may technically be the most efficient ranges for growth, they are not practical indoor and all you're doing is setting up for mould and PM issues. I've seen PM take at anything over 55% so that's my max and what I have my dehuey set for during lights off. Regardless of what some chart says, it would probably be fine outdoor, much like our weather here in summer, but not indoor.

Here's the chart btw, in this one the brown/gold areas are the supposedly ideal ranges:

View attachment 4017266

Oh okay, I see. Yeah that's pretty similar to, if not the same ranges of the one I was looking at.

One of the main things I set my attention to on my first grow was making sure humidity was low to avoid any mold ruining everything(which i accomplished but the plants did not seem to like the dry air much. Didn't do much growing And leaves were kind of brittle)And of coarse being a part of riu I am always learning more, on top of what I see from YouTube. So as it was bound to happen, I started focusing on this "vpd" that these growers are talking about and seeing their astounding gardens, and that they're able to keep their humidity up to provide this because of a couple various reasons, one main one they're always saying is temps.
So now that's basically where I'm at, I want to know and learn how they are able to do this indoors and keep mold at bay while causing much more healthy plants and higher yield.

 

[GroErr]

Oh okay, I see. Yeah that's pretty similar to, if not the same ranges of the one I was looking at.

One of the main things I set my attention to on my first grow was making sure humidity was low to avoid any mold ruining everything(which i accomplished but the plants did not seem to like the dry air much. Didn't do much growing And leaves were kind of brittle)And of coarse being a part of riu I am always learning more, on top of what I see from YouTube. So as it was bound to happen, I started focusing on this "vpd" that these growers are talking about and seeing their astounding gardens, and that they're able to keep their humidity up to provide this because of a couple various reasons, one main one they're always saying is temps.
So now that's basically where I'm at, I want to know and learn how they are able to do this indoors and keep mold at bay while causing much more healthy plants and higher yield.

Yeah indoor, even with really good and 24/7 airflow, anything over 60% is potential for mould and PM - in flowering. There are other factors like temps relative to the RH that can play into it., basically as your temps go up, you're lowering RH. So lights on it's easier to keep the levels at what you want. Key is to watch RH levels in the dark period, they spike when the lights go off so you have to allow for/manage that. I throw my dehumidifier on a timer, on during lights-out, set to 55% and it fluctuates between 54-58%. Temp/RH sensors I have feed me reads every 15 minutes so I can see what's going on.

I've found good results results and general healthy plants running 78-82F/50-55% RH in flower. In veg I go more like 75/65 and get decent results. They'll grow/flower in a wide range though, watching RH doesn't get too high in flower is the one you mainly need to monitor.

Here's an example of what I'm pulling in that environment, just harvested this bunch, 6 plants, 5 strains 3 & 5gal pots.

 

[Lightgreen2k]

@stoned-monkey @GroErr basically answered you and what I was going to say..

Put it this way, Fungal diesease as a hold is easy to catch with high humidity. There are a few of them too

 

[ttystikk]

Your low humidity is caused by excessive air turnover in the room. An environmental controller will help sort this out. Using the room air turnover to control temperature will always be a compromise, however.

The trick is to remove the excess heat without turning over the air in the room. This will keep the humidity in the room and it will allow/force you to supplement with CO2. This will also require an environmental controller.

 

[NugHeuser]

Your low humidity is caused by excessive air turnover in the room. An environmental controller will help sort this out. Using the room air turnover to control temperature will always be a compromise, however.

The trick is to remove the excess heat without turning over the air in the room. This will keep the humidity in the room and it will allow/force you to supplement with CO2. This will also require an environmental controller.

So I'm stuck between ordering more cmh's or going with cobs. I know your a cob guy but Im wondering about running 4 315cmh and a de 630 cmh(I've already purchased the 630, at 30" above canopy I'm peaking at 84 degrees and we've had some of our highest temps all year the past few days, 90s). Inside of a sealed room, is it going to cause heat issues that i cant control? Even puting an a/c in the room makes it no longer sealed because I have to exhaust hot air right? If i seal the room up i will be running co2. The grow area is 4x10, inside of a 9x10 room (all open, no tents or grow area barrier). Would you think that running those cmh in a sealed room would cause an unmanageable heat issue?

 

[ttystikk]

So I'm stuck between ordering more cmh's or going with cobs. I know your a cob guy but Im wondering about running 4 315cmh and a de 630 cmh(I've already purchased the 630, at 30" above canopy I'm peaking at 84 degrees and we've had some of our highest temps all year the past few days, 90s). Inside of a sealed room, is it going to cause heat issues that i cant control? Even puting an a/c in the room makes it no longer sealed because I have to exhaust hot air right? If i seal the room up i will be running co2. The grow area is 4x10, inside of a 9x10 room (all open, no tents or grow area barrier). Would you think that running those cmh in a sealed room would cause an unmanageable heat issue?

I've been able to get away with running a single 1000W HPS in such a room with no additional cooling. It was in a basement, however.

AC need not remove air from the room, depending on the design. If you use a portable, it needs to be a dual hose unit. A window banger doesn't circulate air, it just removes heat. It also dehumidifies, which can be good or bad depending on your situation.

I personally recommend people buy LED lights because they won't be obsolete anytime soon, they're low/no maintenance, no bulbs to replace, more efficient and better quality results.

Quantum Boards and COB LED are both excellent options. Beware the cheap knockoffs!

 

[Enigma]

Misters with a controller or an aquarium.

 

[NugHeuser]

I've been able to get away with running a single 1000W HPS in such a room with no additional cooling. It was in a basement, however.

AC need not remove air from the room, depending on the design. If you use a portable, it needs to be a dual hose unit. A window banger doesn't circulate air, it just removes heat. It also dehumidifies, which can be good or bad depending on your situation.

I personally recommend people buy LED lights because they won't be obsolete anytime soon, they're low/no maintenance, no bulbs to replace, more efficient and better quality results.

Quantum Boards and COB LED are both excellent options. Beware the cheap knockoffs!

Yeah I've done a little bit of researching cobs. It seems that these companies price points out there such as rapidled, cobkits, etc, are pretty similar to just buy the complete ready to ship engines/kits in comparison to buying it all separately and doing a diy, am I right?
If that's the case that would help because between my job and my grow, I really have no extra time to be diy'ing.

I'm pretty happy with the heat output so far of my de 630, it runs cooler than my se 600 hid. The room is in the basement which should work perfect over winter. And my A.C. I have is a portable 8000 btu. It has a hose duct on the back that has to exhaust hot air. It worked fine being ducted to my 5x5 tent but I'm thinking It wouldn't be enough for this room if I needed to use it.

Another question though, I was planning on loading up my grow area with about 45 to 50watts per sq foot, being a higher amount of light per area though, does that mean that I'm actually wasting light/overkill if I'm not running any co2?

 

[ttystikk]

Yeah I've done a little bit of researching cobs. It seems that these companies price points out there such as rapidled, cobkits, etc, are pretty similar to just buy the complete ready to ship engines/kits in comparison to buying it all separately and doing a diy, am I right?
If that's the case that would help because between my job and my grow, I really have no extra time to be diy'ing.

I'm pretty happy with the heat output so far of my de 630, it runs cooler than my se 600 hid. The room is in the basement which should work perfect over winter. And my A.C. I have is a portable 8000 btu. It has a hose duct on the back that has to exhaust hot air. It worked fine being ducted to my 5x5 tent but I'm thinking It wouldn't be enough for this room if I needed to use it.

Another question though, I was planning on loading up my grow area with about 45 to 50watts per sq foot, being a higher amount of light per area though, does that mean that I'm actually wasting light/overkill if I'm not running any co2?

Kits will be cheaper than complete fixtures. Consider the money saved payment for time spent, and remember that you only have to build the light once lol

I like the CMH spectrum. If you're happy with that light, rock it! I think 40-50W/ft² is a good target with CO2 or without.

Your AC unit with a single exhaust house has to get the air from somewhere, and that somewhere is your growroom! Not efficient and it will suck your CO2 and RH out, too. Consider a different unit or feed it a supply of cool air from outside your grow space.

 

[NugHeuser]

Your AC unit with a single exhaust house has to get the air from somewhere, and that somewhere is your growroom! Not efficient and it will suck your CO2 and RH out, too. Consider a different unit or feed it a supply of cool air from outside your grow space.

I see. Yeah I think I will be safe over winter with heat, my basement seems to be freezing each winter although I've never took a temp reading through winter since I just started growing this spring.
However all of the basement except the grow room is cement floors and limestone walls. Grow room is a finished room so that should hold heat much better. I'm going to guess the rest of my basement to be in the 50s through winter.

I'm kind of thinking of going the route of running cmh's during winter and cobs during summer, I'm thinking running cobs over summer so I could steer clear of an ac unit and if I have to I can turn on my intake to blow cool air into my grow room. I would think that cobs shouldn't cause any heat issues even during the summer, what are your thoughts? Probably would go with around 1800 watts of cob, haven't put too much thought into it yet though

 

[ChaosHunter]

Lights, Heat, Cooling, Humidity, are all relative to replicate environmental conditions. Your growing will only be as good as your weakest link. Yes you can MacGyver a setup and chase conditions but it still comes back to the weakest link.

Using lights as a heat source ?What are you going to do when the lights are off ? A heater I'm guessing and if that's the case you might as well use a COB setup year round.

 

[NugHeuser]

Lights, Heat, Cooling, Humidity, are all relative to replicate environmental conditions. Your growing will only be as good as your weakest link. Yes you can MacGyver a setup and chase conditions but it still comes back to the weakest link.

Using lights as a heat source ?What are you going to do when the lights are off ? A heater I'm guessing and if that's the case you might as well use a COB setup year round.

Yes a space heater on a timer is what I was planning.

A big factor with my entire grow, that I have to be careful with is watt usage. I live in a smaller 2 bedroom house alone and normally during summer I'm peaking at 200 dollar light bills and winter is more around 75 to 100(thats before I grew. The previous owners of the house had a shit ton of high wattage home light bulbs all over at every light switch. I switched all those out with 5 watt led bulbs when i started growing and that helped alot). Last grow i was running 2100 watts or so (was a very inefficient grow), on top of central air always on and my bill peaked just over 300 dollars. So point being I don't want to raise any flags. I have my total amt of watts I can use roughly figured at home. I wanting to do my best to always stay under 300 to 350 dollar light bill(summer time will be pushing that amount).

So about the space heaters. From some quick searches on Amazon, they are complete wattage HOGS. I'm seeing a lot of 1500 watt heaters that are pretty damn small(like 10" table top heaters).
Only having to run a heater for say maybe 6 hours during dark time (sealed room should hold heat for a bit after lights go off), or even if it's 8 to 12 hours, beats having to run one closer to 24 hours if I'm running cobs over winter. That's the way I'm seeing it anyway, I don't think those cobs would be able to keep the room heated on there own

 

[ANC]

You could use a hygrostat with both temperature and humidity control.
It has two switched relays that automatically run your heater and extractor fan to control humidity and temp.

 

[ChaosHunter]

Get a plug in seedling mat controller. https://www.amazon.com/iPower-68-108°F-Thermostat-Controller-Germination/dp/B01E9IO6N0/ref=sr_1_2?ie=UTF8&qid=1506626677&sr=8-2&keywords=heat+mat+controller

Dial in what you want your temps at, put the probe in your grow space.

Humidity/dehimidity controller
https://www.amazon.com/Inkbird-Dehumidification-Humidifaction-Dehumidifier-Charcuterie/dp/B01FQKXRXA/ref=pd_sim_86_4?_encoding=UTF8&pd_rd_i=B01FQKXRXA&pd_rd_r=EHVV8M235HTEJA0M3XTD&pd_rd_w=HSxdf&pd_rd_wg=0ho46&psc=1&refRID=EHVV8M235HTEJA0M3XTD

Can plug both humidifier and dehumidifier at the same time, lock in your humidity where you want it.

 

[ANC]

https://www.rollitup.org/t/the-hygrostat-thermostat-combination-device.940136/

 

[ttystikk]

Yes a space heater on a timer is what I was planning.

A big factor with my entire grow, that I have to be careful with is watt usage. I live in a smaller 2 bedroom house alone and normally during summer I'm peaking at 200 dollar light bills and winter is more around 75 to 100(thats before I grew. The previous owners of the house had a shit ton of high wattage home light bulbs all over at every light switch. I switched all those out with 5 watt led bulbs when i started growing and that helped alot). Last grow i was running 2100 watts or so (was a very inefficient grow), on top of central air always on and my bill peaked just over 300 dollars. So point being I don't want to raise any flags. I have my total amt of watts I can use roughly figured at home. I wanting to do my best to always stay under 300 to 350 dollar light bill(summer time will be pushing that amount).

So about the space heaters. From some quick searches on Amazon, they are complete wattage HOGS. I'm seeing a lot of 1500 watt heaters that are pretty damn small(like 10" table top heaters).
Only having to run a heater for say maybe 6 hours during dark time (sealed room should hold heat for a bit after lights go off), or even if it's 8 to 12 hours, beats having to run one closer to 24 hours if I'm running cobs over winter. That's the way I'm seeing it anyway, I don't think those cobs would be able to keep the room heated on there own

Run the lights during the coldest part of your local day- that's usually something like 9pm to 9am. A little temp drop during lights off is acceptable.

 

[NugHeuser]

Get a plug in seedling mat controller. https://www.amazon.com/iPower-68-108°F-Thermostat-Controller-Germination/dp/B01E9IO6N0/ref=sr_1_2?ie=UTF8&qid=1506626677&sr=8-2&keywords=heat+mat+controller

Dial in what you want your temps at, put the probe in your grow space.

Humidity/dehimidity controller
https://www.amazon.com/Inkbird-Dehumidification-Humidifaction-Dehumidifier-Charcuterie/dp/B01FQKXRXA/ref=pd_sim_86_4?_encoding=UTF8&pd_rd_i=B01FQKXRXA&pd_rd_r=EHVV8M235HTEJA0M3XTD&pd_rd_w=HSxdf&pd_rd_wg=0ho46&psc=1&refRID=EHVV8M235HTEJA0M3XTD

Can plug both humidifier and dehumidifier at the same time, lock in your humidity where you want it.

I will do this. You put that pretty simple and I appreciate the links, thanks man