Co2 users....Do you drop your humidity temps and co2 the further you get into flowering?

[drknockbootz]

Ive had couple runs recently where I ran high temps and high humidity and co2 at 1100 and my bud quality came out probably worse than ive seen in a long time. These 2 runs im referring to are my first go round with using co2. Its a strain ive been growing for a while Ive had some good and bad runs with this strain and these last few have been very disappointing quality wise,but yielded great.

I was trying maximize my output since I was using co2 and I was also trying to stay in range of the vpd. So mostly throughout flowering my temps where around 81-85(possibly higher leaf temp) humidity in the 60%-70%.
Then I read threads on people saying low temps and low humidity in flowering can aid in increasing resin production and overall quality.
So I guess Im looking for the perfect balance. I want to get all I can out of using co2 and great yields and quality in my finished product.
Just wanted to get peoples opinions on whats worked best for you?

 

[purpleberry]

Enviroment is key to growing and getting it dailed in isnt easy. First having complete control helps alot, You need to be able to set the temp, humidity and co2 to what ever you want. If you cant do that, I would try to make it where you can.
Ive always read to run hi temp and humidity with CO2. I dont care for the really hi temp and like you said what temp you read on the wall is going to be differrent than at the leaf. Any way here is what i do.
First 1-4 weeks im running temps at 75 on the wall probally more like 78-80 under the lights. Same at night. Make sure in the winter your room isnt dropping below 68-70 at night the first weeks. Week 4 i start dropping night temps if i can Week 5-6 i go down to 72 and night temps 65 Last 2 weeks maybe colder. This increases resin, tightens up nugs and adds Color to the strain i run.
Co2 starts out at 800 by week 2 1000-1200 by week 4-5 1500 Then you need start dropping it back down, By the time I start to flush at week 7 Co2 is at 6-800 You can almost match your fert ppms to your co2.
Humidity I run at 60-70% week 1-4 or 5 Then i back it off to %50 If there real chunky purple buds I run it down to %45 to help reduce mold the last 2 weeks.
Most changes i make to the enviroment is done a little at a time over days or weeks. I beleive drastic changes can piss your plants off.
Ive see rooms ran with hi temp and co2 the entire time and It does decrease quaility.

 

[kushtrees]

Here is my weekly environmental layout (edited out some irrelevant info for the thread). The ppms referre to ppms of CO2 not nutes. This is for a 8-8.5 week strain but can easily be adjusted to a 9-10 week one.

You absolutely want to drop co2 the last 2 weeks to the outside level (380-400). This will help with your quality greatly

Veg: 81 F, 70 RH, 1000 ppms

W1-3: 81 F, 70 RH, 1000 ppms

W4: 81 F, 65 RH, 1000 ppms

W5-6: 78 F, 60 RH, 1000 ppms

W7: 75 F, 55 RH, 400 ppms

W8-8.5: 75 F, 55 RH, 400 ppms, RO flush

Hope this helps

 

[midwestdensies]

That is baller and spot on I may rock higher temps in veg and transition this next round to see what I can see. maybe 85-90

 

[Donkdbz]

I run bout same as Kushtrees. I pretty much keep c02 at 1200

veg 82-84F 75-80RH
in Veg I try to keep my VPD between 0.8-0.9
I will measure both air and leaf temp

Done right you will see the most retarded fast growth ever.


weeks 1-3 80-82F 60-70RH
rest of flower 78-82F 50-55RH

 

[Animal Chin]

Just getting off using co2 but I was running it at 1500 til 4th week of flower then I'd just pump fresh air via blower with hepa filter

My temps were 82-84 til 4th week then I'd drop it to mid 70s

RH 75% Veg
RH 50-55% Flower

 

[drknockbootz]

Thats good to see everybody thats posted is running something similiar.
I have a run thats 4.5 weeks in 12/12 I followed pretty close to what most of you guys mentioned.
So far its looking much better than my last two previous runs

1-3 weeks: 81-83F 60-70%RH ......co2 1100
(As we speak) 4-6 weeks 78-80F 50-60% ......co2 1100
Last two weeks 72-76F 50%RH ....turn co2 off and flush


I see must of us run high humidity.
Also anyone try low humidity last two weeks lets say 40%?
Can anyone explain why somebody as smart as fatman was saying to run humidity at 30%-40% throughout flowering.

Just wondering has anyone ran humidity low while using co2.

 

[mastagrowa]

You should always keep humidity low (30-50%) regardless of CO2.

In my several years' experience with running sealed rooms, I'd recommend starting out high CO2 PPMs (1300-1500) then tapering off if possible, finishing at 800 PPMs for the last 2 weeks of bloom.

In my setup, however, since I run half the trays at different schedules to get a perpetual harvest, I can't do that...but I've found that moderately high (1300 PPMs) through til finish doesn't hurt anything....

 

[purpleberry]

• mastagrowa I think your way off on humidity Around %45-50 is a good Low end. Why do you think plants grow so fast in the rain forest or in a green house and why they use misters, Plants love humidity.
• Some growers will say you have to have low humidity because there affraid of mold issues. Thats a whole other issue and shouldnt be used as a reason to say you should have low humidy. If you have mold I guess you have to run it low. And %45 will prevent mold and slow it down, No reason to go lower.
• I hear you if you have to run a perpetual room, But I base alot of how i grow off of changing the enviroment at different stages of growth and I would hate to have to run the same all the time. Ive tried to talk a freind out this for years and he wont give it up. At the same time asks me how to fix problems that are caused by it. LOL

 

[mastagrowa]

Purple, I respectfully disagree about humidity ;) If our plants really loved that much humidity, we'd be buying humidifiers, not dehus! Anyway the fact that plants grow well in the "rain forests" has little to do with indoor cannabis, which actually flourishes in a wide variety of climates...That said, you could safely stay at 45% and be safe. The mildew/mold prevention is really the reason. But 70%? nah...dangerous.

 

[youngtrader9689]

masta what temps are u at for your perp

 

[woodsmaneh]

Here is my weekly environmental layout (edited out some irrelevant info for the thread). The ppms referre to ppms of CO2 not nutes. This is for a 8-8.5 week strain but can easily be adjusted to a 9-10 week one.

You absolutely want to drop co2 the last 2 weeks to the outside level (380-400). This will help with your quality greatly

Veg: 81 F, 70 RH, 1000 ppms

W1-3: 81 F, 70 RH, 1000 ppms

W4: 81 F, 65 RH, 1000 ppms

W5-6: 78 F, 60 RH, 1000 ppms

W7: 75 F, 55 RH, 400 ppms

W8-8.5: 75 F, 55 RH, 400 ppms, RO flush

Hope this helps

The only thing I would change is the flush with RO, use just water, RO has nothing in it and your plants could use a little something in flush.

Note Using straight RO is a bad idea as it is difficult to Ph due to it have nothing in it. We have a whole discussion over on the UnderCurrent forum about RO. You should always add 25% regular water to RO.

How to buffer reverse osmosis water
Here is a great tip for those who use reverse osmosis water to buffer your water and help stabilize pH. There are two ways, both efficient.
- For those who prefer simplicity, all you have to do is add 20% tap water to your reverse osmosis water.
- For the purists who do not want to use tap water, or whose water is particularly bad, here are two easy steps:
1 – First increase your pH up to 10.0 with pH Up or potassium carbonate
2 – Then bring it down to 6.0 with pH Down
In both cases you’ll obtain water well adapted to hydroponic nutritive solutions, while avoiding untimely pH fluctuations.
You need to raise pH first because the “buffer” elements have a very high pH or very low pH. You can start by adding acid, but then you will need pH up to raise your pH.
You need to buffer R.O. water simply because pure water has no buffering capacity. It is subject to big swings in pH every time you add something to the solution, making it unsuited for cultivation. Using pure R.O. is a classic source of failure.

If you’re using reverse osmosis water, add 50-100 ppm of Cal/Mg; this helps to buffer your water so nutrients absorb better. From Advanced Nutrients site http://www.rosebudmag.com/hydroponic-tips-ideas/insider-tips-for-maximum-yield-in-urban-garden

What happens is that the basic/alkaline components (mainly calcium) that are responsible for the high PH (as in 7.3 or 7.6) also buffer it together with the more neutral components. As soon as you add SOME acid, the basic elements neutralize it in 24 hours, but loose some potency, respectively get eliminated partially within the "reaction". If you repeat that process, the alkaline components- and their buffer capacity get lower and lower until the alkaline buffer is "gone". The "last" time you add ph-down/acid to your water, it will drop drastically to perhaps under 5. This mostly happens when a week PH down is used repeatedly. With Nitric acid at 75 or 95 %, this will not happen, it will get the alkaline elements down in one shot. But that is the stuff that burns through concrete floors like alien blood and it's truly not everyone's cup of tea. If ever you can lay hand on it in the US without an explosive license. ;-)
PH of boiled water of 8.4 after 13 hours of boiling is "normal" because you evaporate lots of water, while calcium and other alkaline elements (already responsible for the high pH) remain in the water and hence will be present in higher concentration and push up the pH. There may also be some chemical reaction and transformation within these 13 hours of boiling, I don't know of.
Nutrients generally lower and buffer a certain pH, that's what any mineral composition with an acidic sum, added and dissolved in water does anyway. NUTRIENTS are actually made to lower the PH, as the usual 7+ is not suited. The only difference is that some manufacturers point this out explicitly while others don't. Some manufacturers may indeed add some more of specific components like mono potassium phosphate that helps lowering and buffering such Ph, but that's pretty much it. As a side effect (when running higher EC) you may have excessive Phosphorus that will result in Ca deficiency.
But in this context it is important to know that a higher nutrient concentration will lower the pH more than a weaker ratio. Hence in some cases it's not a bad idea to simply (slightly) increase the nutrient concentration by a click or two. It's also a reason why some manufacturers recommend higher concentrations as needed, and some commercial growers push the nutrient concentration higher.
If the PH of the base water is too high, most nutrients can't bring it down to around 6 and that's (only) where pH down- as in acids or other components are required. In ANY case it is always best to have, use or get water that is around and not (much) over 7.
RO water is fine, but take care what nutrients you use, as with some extra acidic nutrients (many are developed with areas in mind that have an excessive amount of calcium carbonate in the (well)water) you may end up with an unwanted but extraordinary low PH as well.
Attention, Ph and EC are interconnected, EC reading of a nutrient solution will not be the same at PH 5.0 as it is at 7.0!

 

[kushtrees]

I agree with you, but my tap is bad and I'm lazy. I usually add RO to my last week of nutes to dilute it down to about .2 EC and pH it. Once that runs out its RO for the last couple days.

 

[mastagrowa]

masta what temps are u at for your perp

Keep em pretty much at 75-80 throughout bloom...lower night temps get you more purple/blackness in the flowers....