plant Can’t fix leaf curling

[TouchedMyEyes]

2 of my older & larger plants are exhibiting significant leaf curling amongst another 16+ that are doing fine.

I’ve tried making sure they are pretty dry before watering again (at the time of taking these pictures, the containers are pretty light and I feel they would need to be watered soon).

The lights are at 300 PPFD for 18/6.
No purple leaves and not much else is curling up, definitely not to this extent.

Should I be looking elsewhere as to what’s causing this? Or just back off on the lights for a week and see what happens?

 

[Marturo]

Do you mist your plants?

 

[TouchedMyEyes]

Do you mist your plants?

I have done foliar sprays

 

[HerbCasa]

Maybe the plants are retaining water in the leaves

Or they each might have different issues
Are they doing any better?
You might want to isolate them if they might be infected with a virus or something.
I don't really know
Just trying to guess

 

[Marturo]

Look at the color of this plant. I have had many young plants curl their leaves & then grow out of it.

One tip that works very well for us. Use 1 teaspoon per gallon in your misters & water jugs.
This will be the fourth season we be using this product.
0. Fungus Gnats.
0. fungal problems.
Worth a try.

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