LED and minimal day/night temp fluctuation

CBDgold01

Member
small is good - but a solid, well insulated chamber with a reduced min. airflow will help you to keep higher temps.

real 300W led-light still means ~225W (~75%) of produced heat + ~75W(~25%) light, which then is converted to heat on the surface of the inlighted area, if it doesn`t serve for photosynthesis.

Avoid cool incoming air blowing onto wet roots. Keep them as dry as possible .They are the most sensitive part of a plant against cold. The micro-organisms don`t like it cold either
and insulating the bottom of your pots with a piece of rigid foam can help to keep them more activ.

In summer it`s good to have the incoming air at the bottom and outgoing at the top.
In winter you should use some meters of fan pipe to manage your airflow vice versa.

Some growers using the heat of the outgoing air to heat up the ingoing air with a selfmade heatexchanger.
A few days ago I reversed airflow (as in pulling new warm air from top, exhausting from bottom. Got temps to 75-80 lights on / 66-70 lights off.

I now added in another light and have temps 80-84 lights on / 66-70 lights off.

I'm kind of pissed they dont put the recommended temps on their site along with all the other relevant info such as height you should keep light. (they recommend 85-87 degrees)

I would have saved money and used the HPS I already own since its winter. I'm roughly half way through flowering and it's looking like yield is going to greatly suffer. (up until about half way lights on temp was 70-72/lights off 65-68 (I knew this was too cold but didnt realize how much worse these temps are for LED). These only seem to be good for growing when its warm. I really don't understand how small time growers can use these things in the winter when house temps are like 72 at best.
 
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CBDgold01

Member
@Moflow post some of your plant pics and what they look like in winter!! :bigjoint:
I'd like to know what their day/night temps are! I'm doing everything by the books. Plants look super healthy. Just not developing buds well. Super smelly, nice shade of green, zero nute burn, frosty as a mug...

how much temp drop do you reccomend? The warmer I get my tent lights on the cooler itll be lights off.

Ive got it up to 80-84 lights on, and it'll see a 10-14 degree drop at night now
 
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coreywebster

Well-Known Member
I'd like to know what their day/night temps are! I'm doing everything by the books. Plants look super healthy. Just not developing buds well. Super smelly, nice shade of green, zero nute burn, frosty as a mug...
Frosty as a mug.. lol I haven't heard that one before!

Got some pics? Don't see how its your temps if plants are healthy. How far are the lights from the plants?
You sure its not a lack of co2? That will happen when venting back into the room.
 

CBDgold01

Member
10-14 degrees drop is fine. Below 65 is when things start to go to shit and below 55 they can die.
Different strains will tolerate different temps better or worse.
Lack of co2 is possible I suppose, but its only like 4, 15 inch plants. they're not tiny, they fill up the 20x36 inch area well but I'd be a little surprised if that is the issue
 

CBDgold01

Member
10-14 degrees drop is fine. Below 65 is when things start to go to shit and below 55 they can die.
Different strains will tolerate different temps better or worse.
If it's lack of co2 im gonna feel like such a jackass. Thats so much easier to solve than temps for me
 

Krytend

Well-Known Member
As long as you're between 85-69 I wouldn't worry too much about the temps just make

sure you get lots of air exchange. There's a huge difference between optimal and

acceptable temps ,sure if you could keep your temps at 81 on and 75 off that would be

perfect but it's hard to do in a tent for sure. I've never had a problem with fluffy buds with

too low of temps only too high temps. Also never listen to anyone who suggests to turn your inline off or only run it for a certain amount of time it's a bad idea for many reason.
 

CBDgold01

Member
As long as you're between 85-69 I wouldn't worry too much about the temps just make

sure you get lots of air exchange. There's a huge difference between optimal and

acceptable temps ,sure if you could keep your temps at 81 on and 75 off that would be

perfect but it's hard to do in a tent for sure. I've never had a problem with fluffy buds with

too low of temps only too high temps. Also never listen to anyone who suggests to turn your inline off or only run it for a certain amount of time it's a bad idea for many reason.
my inline runs 24/7 on lowest speed, always has always will

Ive got temps up and im exhausting old air farther away now.
I realized I started seeing less growth after I put a second carbon filter on the end of my exhaust duct (day 7ish flower). There was still fresh airflow to the tent but it was probably not adequate because most of the old air wasnt being blown out of the closet anymore, just dispersed on the other end.

I'm guessing my problem was part temps but mostly lack of fresh air.

I feel like a total tard. I didn't realize how much less fresh air it was getting because of this until today. Although I am a newbie (this is my second grow) I did everything right....until I added a second filter because of smell. The buds arent tiny wisps or anything but I know they are not as big as they should be at day ~28... sigh. live and learn.

I hope the next 30-35 days will be enough to give me somewhat satisfying buds. They look to me like theyre roughly 7 days behind.
 
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Moflow

Well-Known Member
What day of flower are you in?
Around 25 days, 3 RQS Royal Gorrilla and a Sensi Star original.
They are under 5 x cxbs at 200 watts and are around 6" - 150mm from the light.
I have the plant pots on top of a 2" - 50mm block of polystyrene.
I also have a large heat mat I can use if it gets really cold but I haven't used it yet this autumn, although I will come November December.
I have a 12v pc fan and a bit of ducting pulling the hot air from top of tent and discharging it onto the plants below.
20181025_172829.jpg
Perhaps it's the strain you have growing? What type is it, sativa- ish?
Maybe your 8 week strain is really a nine weeker?
Some people believe the breeders times for when a plant is ready when it could go another 10 days to 2 weeks longer than it sez on the packet.
I think your plants look ok by the way :D

I'll post pics of temps later
 

Moflow

Well-Known Member
Min Temperature, lights off.

20181026_131224.jpg
Temp now, lights off

20181026_131235.jpg

Lights on, Temps
20181026_131243.jpg

So around 10°C - 50F lights off
And around 27°C - 80F lights on
 

Krytend

Well-Known Member
View attachment 4221605 View attachment 4221606 View attachment 4221608

These are roughly 28 days (4 weeks) into flower.

They aren't teeny tiny little buds, they're taking shape, but the mass is really lacking. Hasn't been much growth the last week, maybe week and a half.

If you zoom in you can see they aren't really filled out that well for the age.

With 4 weeks to go what kinda shape do you guys think I'm in with Co2 and temp issues addressed?
They look good to me man also some strains really pack on weight at the end.

I've got a glue cross that looks like nothing till week 5 then goes ham.
 
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