Spots on leaves: anyone can help me identify the problems?

[Matfkn]

Hello, can someone help me identify this problem?
Plants 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.

 

[r0am1ng st0ner]

Have you ever got nutes on the leaf while lights on? Is this the only leaf effected? Watch to see if it spreads but sounds like you are on top of it

 

[BeanTownFan420]

Careful with the diatoms wear safety mask they damage your lungs when breathed in cover your eyes with scratch your eyes too.

 

[Matfkn]

Hi ,

Thanks for your replies, roam1ng no I never sprayed them, only the time when I applied the bug repellent, and I did it when the light was off, 2h before cycle begin.
Are different leaves and as I mentioned probably is thrips still doing their things.. Just want to double-check with some more experienced than me. I was thinking of nutes burn or some deficiency like calmag maybe?

Bean I already did the treatment and yes I used a protective mask and I was VERY careful.
Pics of the whole plants 5 days ago..

 

[r0am1ng st0ner]

looking at her leaf tips I dont see obvious nute burn but I have never had thrips so I can not advise there.

I don't see any of these deficiencies on her