What the hell is this

[BigB6]

This is my first attempt at DWC.
Lights are migro cob 400
I'm using advance nutrients line at half strength
Water temps always 18
Ppm around 1100
Ph always in range
This is the Mexican airlines strain from fastbuds.
It started off great but started to develop brown spotting and eventually led to this. What is it?
I was giving the thing calmag.
Should I just dump it or will it be able to mature given the fact it has pretty much no green left. It's in the 3rd week of bloom.

 

[Jackson]

I had plants look like that and it turned out to be a ph problem. Hey if u are using a probe to check ur ph make sure it’s working properly or calibration may be needed. Like mine years ago it looks like a blow torch hit it

 

[Free Flow]

I'm no expert but lockout is always an issue in hydro. Just because everything else is right doesnt mean there cant be any issues. I've had some plants do this to me where they completely lock out, even after flushing and going back to "doing things right" it never seems to look any better. The bud should turn out b+, still decent for meds given the circumstances. Try flushing and dropping ppms to 8-900 with the addition of some superthrive or something similar. Take what I say with a grain of salt, I'm just a pot head lol. The infirmary can give you a concrete answer, I hear some of the real plant whisperers hang out in there.

 

[Faceoff_one]

Experiencing the EXACT same thing rn, brother. This plant was already stressed into an early flower... I think. And yes I most likely watered my plants with much more acidic water than I should have. An issue with a different plant makes it more obvious to me. I went ham last night on all the nasty leaves like that which was about 30% of them luckily I guess. Buds look better from more light to them and healthy leaves though so whatever.