Spots

[Iamthejazz123]

I have a Seedsman NL Auto, 16 days since breaking ground.
36"x20" grow tent
600w (200 actual draw) Roleadro full spectrum LED @ 24" above the plant.
3 gal fabric pot, FF Coco Loco (Soil/Coco/Perlite mix, NOT pure Coco.)
I feed when the pot is dry on top and light when I pick it up, usually 3 to 5 days between watering.
I water with pH 6.3-6.8 as per FF recommendations for this mix.
I add a tsp of FF Grow Big and a tsp of FF Wholly Mackerel per gallon.
Environment pretty steady around 74 degrees, 50% humidity.
I don't have a TDS/EC meter, so no clue about runoff.

I am getting some yellow spots on bottom leaves, but the plant seems healthy, however I'm worried these spots could be a pest/fungus that could cause problems down the line since it seems to be slowly growing. Any ideas?

Thanks in advance for the help!

 

[Camer41]

Hello. I would look at two things. Is your nute mixture splashing up when you are feeding ? I would also get a small handheld microscope and take a look at the affected leaves. The first photo looks like Thrips. Look for white zig zag lines along the top of the leaves. Use the scope to look under the leaves for asshole bugs sucking up the juices.

 

[Iamthejazz123]

Just scoped the whole thing, top to bottom, no bugs of any kind. I thought I was really careful not to splash onto the leaves, but I suppose it's possible I did. It's odd tho, I've noticed at least one or two of these spots on the 4 plants I've grown over the past 6 months or so, just never so many as have showed up on this plant.

I use city tap water that I let sit for 48hrs, maybe there's something harmful in the water lately that doesn't evaporate and ends up being consumed by the plants?

 

[Bush Doctor 77]

Welcome. Actually looks pretty good. Some of it looks like externally caused damage, not a deficiency. That would be from bugs, physical abuse, or chemical. It really doesn't look like a chemical burn. I'm not seeing it on the newer leaves, which could mean that whatever caused it, ended. I'd give it a dose of neem mix/dish soap just to be on the safe side(not under bright light). Neem is fungicide, insecticide and miticide. It will kill mildews and rusts. You may have had a Ca/Mg problem earlier.

 

[Iamthejazz123]

I think you're spot on with the Cal def. I've seen similar deficiency charts like you posted, but normally they show cal def as brown spots, not yellow. I suspect that's because they're only showing late stage cal issues, and mine are still on the earlier side. Now that I know what I'm looking for, I've been able to find a lot of evidence it's calcium.

Thanks so much!

P.S. Still gonna spray for bugs anyway, can't hurt, right?