HELP! Rusty spots on leaves for Northern Lights Auto Day 40

[ra5h1d]

Hello friends. Need a little help here with my grow. Yesterday I noticed two of my plant leaves having rusty spots on it. The leaves are in the middle section of the plant and about 5% of the leaves are affected. But the other leaves are healthy. Under leaves did not reveal any mites or other pests. I am currently on day 40 since germination. Water mixed with nutrient pH is usually around 6.5 - 6.9. Run off water for the affected plants pH is 6.6. My current provisional diagnosis would be Calcium deficiency. I am using filtered water to water my plants and I am not using any Cal/Mag nutrients currently. Differential diagnosis would be fungal or mold infestation. What do you guys think? I shall be adding Cal/Mag for my next feed.




Grow : Indoor, 4 x 4 tent

Nutrients : Flora series (micro,gro,bloom), liquid silicon, Liquid O2

Grow medium : Regular potting soil

Lighting: Mars Hydro TSW 2000 Quantum board LED. 18 inch from canopy

Temp/ Humidity: 24 - 27 C / 60-75 %

[BlueberryGIrl]

your plants look really healthy! It could be a hiccup, in my grows I have experienced a leaf or two that shows signs of stress and it is only that leaf or two, never going any further. Obviously you are on top of things. Your humidity level seems a little high, do you have a fan circulating air in the tent?

[ra5h1d]

I was hoping it was something that could be corrected easily as fungal infestation is quite challenging. I have two little fans for air circulation and a dehumidifier outside the tent set to 40 percent. Its doing a great job where I have to empty the water reservoir everyday. I have also installed a second air conditioner inside the room where the grow tent is located. I'm living in South East Asia and its extremely hot and humid right now. I'm not sure how else I can reduce the humidity as the plants have grown so much since they started flowering.

[BlueberryGIrl]

Yes, the humidity is a battle! that is humid! definitely good air flow with those flowers coming in. if it is fungus, you are on top of it so that is good and makes the resolution easier. It is unfortunate that you cannot grow outdoors. I'd say given what you are up against climate wise, you are doing well.

I do not know much about autos nor Northern Lights. I would say that given your location, your strains need to be specific to that climate.

[ra5h1d]

You are right. I should look for more hardy strain that is able to withstand hotter temperatures for my next grow. There's an article by Nebula specifically on this if I'm not mistaken. I started with Northern Lights after reading several recommendation that its great for a beginner grower.

[BlueberryGIrl]

I have read that , somewhere, as well about Northern Lights. I made the mistake of beginning my grow career with a sensitive strain. it's all about learning! best of luck with the grow and humidity!

[Canuck147]

I think your plants need the Cal/Mag.

[Tersky]

Was about to post this and found you already had! I agree. Cal mag issue or possibly lockout

[Sledrock]

I think your plants need the Cal/Mag.

That's what I was think too, Canuck.

The other day I had a brown, burnt spot on one my middle l leaves, too ra5h1d I didn't know what caused it? But it was only one leaf and hasn't come back, so I just removed that leaf.

I wish you the Best of Luck ra5h1d!

[ra5h1d]

Thanks guys. I included cal mag on my last feed 2 days ago and so far no new lesions seen on the other leaves. The other girls are doing awesome. So I think it was cal/mag deficiency after all and not rust fungus.