Brown Spots on Older Leaves of Otherwise Vigorous Plant - 4 Pics

Sup everybody, I have this problem that's boggling my mind.

Brown spots appearing on the older fan leaves of an otherwise healthy fast-growing plant, pics shown below.

These spots started appearing about 2 weeks into flowering and keep multiplying in numbers as time goes by, but the plant keeps growing and looks great otherwise.

This only affects the older growth, everything that is new looks perfect with no spots.

And I do not have an ozone generator or ion generator anywhere in my house, so it can't be that.


Here are the setup details:

Strain: El Nino

Hydro: 2-Gal DWC bucket (expanded clay pellets as medium in 6" net pot)

Nutrients: GH Flora, Lucas formula (~950ppm max during full bloom)

Water: 130ppm Tap water (left to sit out for 24 hours before use)

Temps: ~75 during day, ~65 at night

Humidity: ~40-55%


My thoughts are that it shouldn't be a nutrient deficiency because the Lucas formula accounts for everything the plant needs. I thought maybe it could be chlorine toxicity from my tap water but its a fairly low ppm and I let it sit out for 24 hours in an open bucket before use.

Anybody have any ideas??

Any help is greatly appreciated, thanks

Hows the pH? Also it does look like calcium and magnesium issue of sorts.

you ever figure this out....got the same problem.

DRIPS420 said:

you ever figure this out....got the same problem.

Click to expand...

Hey man, I actually tried to correct the issue for months but it never went away. I came to the personal conclusion that I just had a bad seed or mother plant... like it must have had a disease or genetic disorder or something.

I was trying everything and it never got better, and I never had an issue like that with other plants.

Hope you figure it out!