Help identifying leaf problem!

Hello!

Gonna start off by saying I know this looks like thrip/mite damage, but I cannot find a single one, even checking on the plant 10 minutes before lights on, never to be found.

And it looks like it's be an army causing this damage. Due to the consistent nature of the problem, I'm thinking nutrients, but unsure if deficient or toxic. That or it's a root type issue.

Grow conditions:
Vivosun VS1000 Lighting, hanging a bit higher than I'd like (~36" @ 100%), but this plant is a side project to another grow anyways.
Coco/perlite, 70/30 ratio
DynaGro nutrients, following their 2020 grow chart for ratios. Using the ProTekt, Foliage Pro, Mag-Pro, and Bloom.
Started off at 25% and have kicked it up slowly overtime as that spotting on the leaves started pretty early. Now at 100% nutes and it's still a problem that has been slowly growing and spreading. Here are some pictures.

Top leaf, barely starting


Gets worse as you go down to the bottom.








So, yeah it's a consistent issue throughout the plant. I have sticky traps down, no bugs other than the small fungus gnat problem I have. Always just 1 or 2 seen every 3-4 days. Have been using neem oil in spray as well.

One of the leaves is showing what looks to be nutrient burn, so I'm thinking I might have pushed it too far too fast, but I'm not really sure.

Any input is appreciated and I'll try to answer any questions or provide more information if requested!

Maybe a magnesium deficiency, or overload. Have you been giving it cal/mag? Epsom? What kind of soil?

I'd just feed it pure water for a week or 2 and see how it looks, then go from there.

What is your feeding schedule?
Don't feed pure water in coco!!!!

manfredo said:

Maybe a magnesium deficiency, or overload. Have you been giving it cal/mag? Epsom? What kind of soil?

I'd just feed it pure water for a week or 2 and see how it looks, then go from there.

Click to expand...

Just the DynaGro line is all. The Foliage Pro and Bloom come with all necessary micronutrients and the needed calcium. That's why they just have the separate Mag-Pro.

Wasn't planning on adding anything else to keep the balance of nutrients designed by DynaGro in check.

Definitely gonna avoid using plain water since I'm in Coco. Don't need to wash all the nutrients out lol.

MickFoster said:

What is your feeding schedule?
Don't feed pure water in coco!!!!

Click to expand...

Feeding schedule has been 3/4L of feed every 24 hours. Recently the runoff is slower to come out so two days ago I started giving 1L every 24 hours.

The pot seems pretty wet towards the bottom though despite the slow run off. I've been pondering if I'm watering in the right amount, but too frequently? Should mention it's a 2 gallon fabric pot.

Thats weird coco

koalajesus said:

The pot seems pretty wet towards the bottom though despite the slow run off. I've been pondering if I'm watering in the right amount, but too frequently?

Click to expand...

Coco should be fed daily to substantial run off........it should always be wet.
I assume your fabric pot is elevated so it doesn't sit in the run off?

manfredo said:

Maybe a magnesium deficiency, or overload. Have you been giving it cal/mag? Epsom? What kind of soil?

I'd just feed it pure water for a week or 2 and see how it looks, then go from there.

Click to expand...

Oh sorry, I didn't see you were in coco!!

Bukvičák said:

Thats weird coco

Click to expand...

It was a brick to start, so I had to wash/break it up and stuff. A lot of fine/dust coco though, so it was a pain to wash out. I messed up in settling for the finer grade perlite too. Home Depot didn't have the coarse grade like their website said and I just folded for what they had. Not doing that one again.

manfredo said:

Oh sorry, I didn't see you were in coco!!

Click to expand...

No worries!
Going off your input though, if I had to guess at what nutrient was causing the issue, I'd probably agree with magnesium.

Leaning towards deficiency, but a small burnt tips on one of the leaves makes me also think toxicity.

From what I've read though, chasing down individual nutrients (unless you know you're missing a specific one) leads to a wild goose chase most of the time.

MickFoster said:

Coco should be fed daily to substantial run off........it should always be wet.
I assume your fabric pot is elevated so it doesn't sit in the run off?

Click to expand...

That's the exact information I've seen in my research on coco. Been trying to stick with that as much as possible.

On 3/4L, I was starting to get about 5%-8% runoff in the last week, so that's why I bumped it to 1L and now I'm seeing about 10%-12%.

The pots are on plastic risers to keep them out of it, and I empty the run off every feeding anyways.

I understand it should always be wet, but the very bottom just felt like it was holding onto more water than it should based on how soaked the pot feels. Giving it a pinch like you would a baby's cheek and it'll let out a decent amount more of water.

My thought process leads me to think some combination of salts, coco, and perlite are jamming up the bottom and holding more water and not releasing run off quite right, leading to some kind of root issue. I'm probably just talking out my newbie ass, so take this with a grain of salt.