What is causing these spots?

[waterdawg]

I agree that it may be mag issue. I cured mine with a light mix of epsom salts and water foiler feed. I also add a tablespoon to res at every refill of 135 liters. My leaves showed darker vein structure with lighter tones in between and only lower leafs affected.

 

[jimmyboi]

I agree that it may be mag issue. I cured mine with a light mix of epsom salts and water foiler feed. I also add a tablespoon to res at every refill of 135 liters. My leaves showed darker vein structure with lighter tones in between and only lower leafs affected.

okay im going to flush it out and give it a 24hr just ph balanced water and then new nutrients.

 

[jimmyboi]

that should help correct?

 

[waterdawg]

Im a hydro grower so not much help! Like i said mine cleared up after foiler feed.