Which deficiency or what?

Hey there!
They were happy over sprinklers and under T5 and i moved them in a PVC NFT hydro system, and one plant showed quickly this leave, low leave, one of the first of a seedling. The top of the plant is fine, just 2 or 3 leaves bad.
Light is 400 w MH, there is a bubbler in the mix, water temp is 23°c, pH is 6, EC less than 1. My tap water is 0.1 EC, and i use bio nova nute brand, it's complete.
It looks like not enough O2 in the water, no? But in an other tent with the same system but under led, in have the second picture. Maybe Mg def.

No idea? No one?

John LOQUE said:

Hey there!
They were happy over sprinklers and under T5 and i moved them in a PVC NFT hydro system, and one plant showed quickly this leave, low leave, one of the first of a seedling. The top of the plant is fine, just 2 or 3 leaves bad.
Light is 400 w MH, there is a bubbler in the mix, water temp is 23°c, pH is 6, EC less than 1. My tap water is 0.1 EC, and i use bio nova nute brand, it's complete.
It looks like not enough O2 in the water, no? But in an other tent with the same system but under led, in have the second picture. Maybe Mg def.

Click to expand...

The left leaf looks most like phosphorus deficiency/lockout.
The right leaf is clear insect damage - caterpillars or grasshoppers.

Insect damage can also cause the appearance of nutrient deficiencies, especially if the plant is using a lot of that specific nutrient, at that stage of it's growth.

So in rooting/early flowering that may be phosphorus. During fast growth that may be nitrogen, etc.

I took a very fast feeding caterpillar of a leaf of one of my plants yesterday. I noticed it because the leaf was disappearing fast enough to notice within 1 hour.

It's that time of year.