Browning leaves - Seemingly very specific pattern

[vapoholic]

Hi,

I am trying to figure out what this is. I took a picture of a leave developing it and it seems to be quite specific. It's not only on top leaves, so I am excluding light burn.

I have checked:

Ph.
Under/over water.
Sprayed BT for gnats yesterday (I did not find any, but just to rule that out).
I am using super soil, so I am just watering with pH:ed filtered water. If something i amiss there I am not really sure what to do.

Any ideas?

Thanks.

 

[vapoholic]

Even going through this Cannabis Plant and Pest Problem Solver - Pictorial I can't really get a fix on the issue.

I did not know however that light burn can show also on lower level leaves and that indicas are more susceptible to light burn (I have a 80% indica NL).

I think I'll try turning my bloom ufo off. It's quite strong and I don't have more room to raise the lamps.

The RH in the box is around 45%.

 

[Emilya Green]

its something in your soil I am betting... did you add a lot of calcium to your mix? What recipe did you use? Did you use all supersoil or did you just have it in the bottom with something else above? If you are attempting to go organic, why are you adjusting pH?

my first guess without the answers to those questions is that you have a nitrogen deficiency, caused by something leeching it out or locking it up in the soil.