Hi all, I'm panicking a bit here and don't know what to do so any help would be greatly appreciated!
First, some info:
Strain: Northern Lights auto
Tent: Secret Jardin DP60 (60x90x60cm)
Lights: 4x 2ft T5s 96w
Light cycle: 12/12
Ventilation: 6" desk fan and I also open the ventilation flaps and door from time to time
Medium: Coco coir
My problem: My seedlings sprouted 4 or so days ago and one in particular (the one closest to the light because it's in a bigger pot) is showing signs of what I think is heat stress. The leaves are curled up and have whitish-brown patches, and the rest of the leaf is a slightly darker green. The lights were about 5-6 inches above the plant in the biggest pot so I raised them another couple of inches but it didn't make any difference. I've now angled the fan directly at the plants to try and eliminate the hot spot beneath the lights. Trouble is, I need the lights to be low to give them plenty of light, but they then get too hot! And if I raise them they'll stretch. I can't win! By the way, I've done the hand test and it feels fine to me, also PH is okay.
The T5s do chuck out a surprising amount of heat and so the temperature in the tent is pretty warm. I don't know what it is exactly as I have yet to buy a digital thermometer but I estimate it to be about 80 degrees, perhaps more. The growing medium dries out very quickly as well so I water them a little every day by watering in a circle around the stem (not the whole pot).
Do you agree that it is heat stress? And if so how do I cool the tent down?? Any help you can give me would be great as I'm really worried about my babies! I honestly didn't expect to run into problems so soon
To be honest these pics don't do it justice how bad the leaves actually look. The white-ish areas on the leaves are actually white, it's not just the light shining on them:
This is the one that's in a smaller pot and thus further from the light:
And this is to show my setup and how far they are from the lights:
First, some info:
Strain: Northern Lights auto
Tent: Secret Jardin DP60 (60x90x60cm)
Lights: 4x 2ft T5s 96w
Light cycle: 12/12
Ventilation: 6" desk fan and I also open the ventilation flaps and door from time to time
Medium: Coco coir
My problem: My seedlings sprouted 4 or so days ago and one in particular (the one closest to the light because it's in a bigger pot) is showing signs of what I think is heat stress. The leaves are curled up and have whitish-brown patches, and the rest of the leaf is a slightly darker green. The lights were about 5-6 inches above the plant in the biggest pot so I raised them another couple of inches but it didn't make any difference. I've now angled the fan directly at the plants to try and eliminate the hot spot beneath the lights. Trouble is, I need the lights to be low to give them plenty of light, but they then get too hot! And if I raise them they'll stretch. I can't win! By the way, I've done the hand test and it feels fine to me, also PH is okay.
The T5s do chuck out a surprising amount of heat and so the temperature in the tent is pretty warm. I don't know what it is exactly as I have yet to buy a digital thermometer but I estimate it to be about 80 degrees, perhaps more. The growing medium dries out very quickly as well so I water them a little every day by watering in a circle around the stem (not the whole pot).
Do you agree that it is heat stress? And if so how do I cool the tent down?? Any help you can give me would be great as I'm really worried about my babies! I honestly didn't expect to run into problems so soon
To be honest these pics don't do it justice how bad the leaves actually look. The white-ish areas on the leaves are actually white, it's not just the light shining on them:
This is the one that's in a smaller pot and thus further from the light:
And this is to show my setup and how far they are from the lights:
I agree With Weasel 
