First grow - SOS on leaves curling

[Foxtrot2112]

Hi, this is my first indoor project.
Weather has been so sunny in Chile that the girls have been taken outside for 6 hours and then back to the room.

I have investigated this typo of leave curling but it doesn't fit the criteria of clawing (excess N) and I only water when soil is dry with pH'd water. Been feeding them Bloom organic nutes from BioBizz at aproximately 800PPM

Could it be overfeeding ?
Heat Stress ?
Insects ?

I will quit feeding and just water.
Help appreciated !

Thanks

 

[zBRiCKz]

Definitely looks like nutrient burn. 800 ppm sounds like a lot to me for a plant that size. I would do 450 tops for now.

Flush out the soil and just give plain water for now for a week or two.

 

[Foxtrot2112]

Thanks mate, they needed watering today so just gave them plain 6.2 pH water
Should I keep them at full sun ?