Help Identifying Yellow Spots

Hello, I'm growing 2 clones - Blue Lemonine & Pineapple Breeze. 2x2x5 tent, Mars hydro ts1000 light, grow medium is ff ocean forest. I've watered them twice and I'm at the end of week 2 since transplant. Using a humidifier to keep humidity between 45-60 and Temps vary from 75-82 or so.

Both plants were doing great until noticing the yellow spots on the blue lemonine. Seems to be spreading to other leaves in a short amount of time. Any help is appreciated.

Maybe no connection but it looks like air inlet vents are closed. 2x2x5 space would need 20 CFM for minimum air change and preferably more. Inadequate air changes would be detrimental but no idea what symptoms would show up first.

Happened upon this, although the article is in reference to aquarium plants...

CO2 absorption happens during the day when the light is on and plants are actively photosynthesizing. There is no need for CO2 injection at night. The main symptoms of carbon deficiency are: (1) necrosis, (2) chlorosis, (3) stunted growth, and (4) twisted leaves.

FreshOffTheCut said:

Hello, I'm growing 2 clones - Blue Lemonine & Pineapple Breeze. 2x2x5 tent, Mars hydro ts1000 light, grow medium is ff ocean forest. I've watered them twice and I'm at the end of week 2 since transplant. Using a humidifier to keep humidity between 45-60 and Temps vary from 75-82 or so.

Both plants were doing great until noticing the yellow spots on the blue lemonine. Seems to be spreading to other leaves in a short amount of time. Any help is appreciated.

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The yellow spots are likely the early stages of a Ca deficiency. Could be due to insufficient Ca, or it's unavailable due to pH or watering issues.

The leaf spots have nothing to do with CO2 or air exchange.

I have similar leaf spots to these on my plants, I'm not sure what it is, but I know my plants are not Ca deficient: also pH is fine with the use of dolomitic lime in the potting mix. I was wondering about trying some fungicides.

I'm planning on a final blooming before restarting with new seed for any subsequent crops. Such future crops will be subject to increased rigor with respect towards sanitation.

simpleleaf said:

I have similar leaf spots to these on my plants, I'm not sure what it is, but I know my plants are not Ca deficient: also pH is fine with the use of dolomitic lime in the potting mix. I was wondering about trying some fungicides.

I'm planning on a final blooming before restarting with new seed for any subsequent crops. Such future crops will be subject to increased rigor with respect towards sanitation.

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After doing some research, I'm kinda leaning towards the fungus side - leaf septoria.

I thoroughly cleaned my tent before set up, used new medium, and made sure it's all buttoned up. Only thing I can think of is being a clone, I brought it home with possible spots already but unsure. Don't know where to go from here to help remove it. I cut any fan leafs that would be "contaminated" so we'll see in the next few days how they do.

FreshOffTheCut said:

After doing some research, I'm kinda leaning towards the fungus side - leaf septoria.

I thoroughly cleaned my tent before set up, used new medium, and made sure it's all buttoned up. Only thing I can think of is being a clone, I brought it home with possible spots already but unsure. Don't know where to go from here to help remove it. I cut any fan leafs that would be "contaminated" so we'll see in the next few days how they do.

Click to expand...

I'm soaking all cutting tools in 20% bleach per TUMI, and I've been noticing I developed sloppy nutrient handling techniques, so I'm re-thinking handling processes. It was 2 weeks ago I drenched root ball with a little dissolved neem oil. Azadiractin is supposedly systemic and can skew the flavor of buds (so I've read). My plants are in vegetative growth, so not worried about that yet. Neem odor is somewhat persistent when applied as potting mix drench. Peroxyacetic acid may be useful: