I need help, yellow stains in the leaves center and I can't increase humidity.

[waimankkkk]

Substrate: Growmix Multipro

Fertilizer: Fishmix | Applied only once, about 0.3ml in total

Lighting: Led Cob Fullspectrum 300W

Humidity and temperature: 22ºC ~ 27ºC and 35% ~ 45%

pH: 6.5

Ventilation: 6 inches - no filter

Genetics: CBD Auto Compassion Lime

Type of Seed (Automatic or Photoperiod): Automatic

The oldest one is 8 days old, it started these yellow spots 2 days ago, I don't know what it is or what to do.

My grow is inside a closet, I know the walls are white now, but today I'm going to put Mylar to improve the reflection, however I can't increase the humidity in any way, it always stays below 40%, I don't know if it's because it's not well sealed, or the LED, or the extractor.

I bought a small humidifier, it made no difference, I bought a bigger one now, same thing, what to do?

Thanks to everyone for the help.

Edit1: I turned everything off and let the humidity reach 80%, then I only turned on the LED and in 5 minutes the humidity dropped to 40%, what can I do?

 

[Creeperpark]

Substrate: Growmix Multipro

Fertilizer: Fishmix | Applied only once, about 0.3ml in total

Lighting: Led Cob Fullspectrum 300W

Humidity and temperature: 22ºC ~ 27ºC and 35% ~ 45%

pH: 6.5

Ventilation: 6 inches - no filter

Genetics: CBD Auto Compassion Lime

Type of Seed (Automatic or Photoperiod): Automatic

The oldest one is 8 days old, it started these yellow spots 2 days ago, I don't know what it is or what to do.

My grow is inside a closet, I know the walls are white now, but today I'm going to put Mylar to improve the reflection, however I can't increase the humidity in any way, it always stays below 40%, I don't know if it's because it's not well sealed, or the LED, or the extractor.

I bought a small humidifier, it made no difference, I bought a bigger one now, same thing, what to do?

Thanks to everyone for the help.

Edit1: I turned everything off and let the humidity reach 80%, then I only turned on the LED and in 5 minutes the humidity dropped to 40%, what can I do?

I love growing in closets much more than tents. Your problem is due to watering. When putting little plants in large containers the watering holding capacity is more difficult to maintain.

Starting plants in small dixie cups is much easier to keep from over or under-watering. When the plants get larger I up-pot into one-gallon pots and then 3 to 5-gallon posts after 6 to 8 weeks..

 

[early_bird]

The white is perfect, may better than medicore installed mylar.
Humidity depends on conditions outside of the cabinet.
May it helps lower your ventilation a bit, hard to judge from here.

 

[goingrey]

Let them grow bigger and humidity around them will increase..

Do the stains wash/wipe off by any chance?

 

[GF-Z]

What is your humidity in the room ? Low humidity is not good for hoomans. We like it close to cannabis, same with temperatures. (in most cases ~22-25).
I have similar closet, and bough some smart humidifer Levoit S300 (good deal) so I just put nessecery %RH on application in phone and humidifer keeps it constantly. Like I put 60~ So humidifier push it to 65% and then lets it to drop to 55% and then starts again till 65%... So it keeps it around 57-62 constantly. Plants are more than happy now.
But in my case humidity in room is around 46-52% so it is easy for him to do the job. Maybe try to use 1 in room to help raise it..
And how much air circulation do you have?
For cabinet like this you dont need more than 100m3/h
I run 2 cabinets with 1 100mm inline ventilator without problems.

 

[TanzanianMagic]

Substrate: Growmix Multipro

Fertilizer: Fishmix | Applied only once, about 0.3ml in total

Lighting: Led Cob Fullspectrum 300W

Humidity and temperature: 22ºC ~ 27ºC and 35% ~ 45%

pH: 6.5

Ventilation: 6 inches - no filter

Genetics: CBD Auto Compassion Lime

Type of Seed (Automatic or Photoperiod): Automatic

The oldest one is 8 days old, it started these yellow spots 2 days ago, I don't know what it is or what to do.

My grow is inside a closet, I know the walls are white now, but today I'm going to put Mylar to improve the reflection, however I can't increase the humidity in any way, it always stays below 40%, I don't know if it's because it's not well sealed, or the LED, or the extractor.

I bought a small humidifier, it made no difference, I bought a bigger one now, same thing, what to do?

Thanks to everyone for the help.

Edit1: I turned everything off and let the humidity reach 80%, then I only turned on the LED and in 5 minutes the humidity dropped to 40%, what can I do?

That's Mildew & Mites.

The rings are a clear fungal/bacterial infection. And mites to track around the spores.

 

[exoticrobotic]

The rings are a clear fungal/bacterial infection. And mites to track around the spores.

Those tiny white spots could well be mites/thrips.

But those brown areas look a result of the low humidity, low watering.

With those massive pots and tiny seedlings the roots are shallow so they likely remain dry while the bottom of the pot remains quite wet.

Scoop them out and repot to a smaller pot and water with a 50% nutrient solution.

Also, get some foam tiles on the floor so your pots are on a warmer surface and insulated a bit.

Roots like to be dark and warm.

Are you sure the pc fan is mounted to draw away from the led unit and not to blow dry air downwards onto the plants?

 

[TanzanianMagic]

Those tiny white spots could well be mites/thrips.

Agreed.

But those brown areas look a result of the low humidity, low watering.

Low humidity and mites and anything mildew go hand in hand.

 

[TanzanianMagic]

I overlooked the

Humidity and temperature: 22ºC ~ 27ºC and 35% ~ 45%

I overlooked that. 35% humidity is low - the plants need a thorough watering.

You should water them slowly until the medium is completely saturated, then not water again until the top of the medium is dry in the morning, which could be in 3 to 7 days at this stage of growth. Which means all the water moving up through the medium from the lower layers is exhausted and you need to repeat.

pH: 6.5

I like to err on the side of 7.0, which allows for more uptake of mobile nutrients (N, P, K, Mg).