Leaves spots! Help to identify this problem / s ?

[Matfkn]

Hello, can someone help me identify this problem?
Plant are auto grapefruit from FastBuds on day 40, in 11L soil (canna professional with extra perlite) pots, under hps (400w in cooltube)till 2 days ago , switch to LED (mars hydro ts 3000) due to external hot temperature.
Nutes schedule A+B (bloom) and explode , both from Dutch Pro, followed producers chart, ph in range on 6.3 , ppm (last) 712 .

Probably I had thrips, used a bug repellent spray and add a layer of diatomaceous earth to the soil aprox 10 days ago (I understand that it blocks their life cycle) .

Here some pics of leaves , what do you think ?
Thanks in advance.

 

[Matfkn]

Shall I post it on a different section? "Autoflower" or "plant problems" ?

 

[myke]

THRIP damage,a little heat stress.WHAT is your question ?

 

[Matfkn]

Hi Myke,

Thanks for reply, question is what can cause those spots ? You think is thrips still doing their thing plus some heat stress ? Not nutes burn or calmag deficiency ?

 

[myke]

Hi Myke,

Thanks for reply, question is what can cause those spots ? You think is thrips still doing their thing plus some heat stress ? Not nutes burn or calmag deficiency ?

Hard to see,but thrips will leave those spots

 

[TessaMaria]

Can you post pictures of the whole plant? Do you see any bugs under the leaves?

 

[Matfkn]

Hi, that’s the point, I was unable to see any bugs/larvae or black spot (poopoo) under leaves, in my opinion plants look healthy, pics are from 5 days ago, while those are from today , but I’d like to different opinions from someone more experienced than me. Thanks