Spots on leaves….unable to find this one

I’ve got a problem which started with one plant only. (I can’t find any photos that look like this) it is almost dead now. The leaves finally all get this & die…
Now, a 2nd plant (a really good one, too!) has it.

here are the photos.

Anyone have an idea what it is? I don’t think it’s Manganese, which is the closest photo.

thanks bunches!

I thought I had more, but here is what I can find.

Looks like late stage magnesium issue.
What is your water source ?
What nutes are you are using ?

Budzbuddha said:

Looks like late stage magnesium issue.
What is your water source ?
What nutes are you are using ?

Click to expand...

I have other leaves showing classic magnesium deficiency. I added Magnesium last week. Not sure if any more have that. This never looked like that. It started with the very black spots in the center vein.

I use tap water (it is low in chemicals, thank goodness). We’re in the country.

OH, I forgot to add that it’s been 100+ degrees here since mid June. The nighttime lows are only around 80. A lot of leaves have heat stress.

I had a photo of the first one, ….but, I deleted some last week & it looks like that may be one of them.

Using Fox Farm Grow Big. I’ve used those for years. This year I have 32 (almost 31) plants.

thanks for your reply & help

I haven't looked yet but I'm trying to get people that have weird leafs that they can't identify to look at the picture of HLV. My guess is that since it started in California and Oregon it will be all over the country in just a year or two. Did you grow from seeds or clone? From what I've read so far it's spread mostly by clones.

People are going to have to know about this because it is coming. I'm going to google HLV photos now to see if one looks like this.

Pics of the newer growth helps, a few leaves at the bottom isn't much to worry about.

Looks like a hungry plant for P and K to me.

I’d switch to bloom food personally. A lot of time outdoor the transition starts earlier than we think. The plants start need higher levels of P and K a couple weeks before full flowering.

idk I’m new to outdoor. Butespecially if it’s hot I’d be feeding feeding feeding right now.

Just found what it is……after applying fertilizer with magnesium added: (THEN I looked it up )
calcium deficiency. Photos showed early deficiency (online,not rollitup )