Can't figure out these brown spots please help

My leaves develop brown spots late in veg and it gets worse through flowering and the eventually get crunchy and brittle. Anyone know what's going on? I'm using ro water and Humbolt county's own nutes and fox farm soil.

My best guess is the combination of RO water and nutes is dropping your ph too low and the plants are locking up. Do you use a ph meter?

CAn you show pics of the entire plant, especially the pot it is in? Are all the plants like that? What has your fertizlizer schedule since you flipped to 12/12? Please post a bunch more pics, it looks like multiple deficiences, perhaps ph related or pot related.

15 gal airpots. Watered every day if needed. Ph of nute mix is usually 6.5. I have one plant in a 20 gal regular pot doing the same thing. My PPM's are around 1000 and I fertilize twice and water on the third day

Older plant leaves

Younger plant

Another pic

It looks like a trace mineral deficiency.. It's hard to tell. But that's where I would start

I'm not sure what to get to add trace elements.

trace elements are your azomite. Dolamite lime humic acid. Etc. Etc

A good hit of nutes.

That on the leaf pic. Shows its lacking p and k. Which can throw your plant way off. P

your using an organic soil. So make sure your nutes are for organic growing.. I'd grew a tea feed em and do a foliar spray with it also

How many ppms of cal/mag are you giving her?

There are some minute white spot underneath your leafs, check at a more powerful magnification they could be mites , some type of mites will cause your plant to react like they have some nutes problem.

Problem: Signs of a cannabis calcium deficiency can be hard to pin down since calcium deficiencies are often accompanied by magnesium, iron, and other deficiencies. However, some of the major signs of a calcium deficiency are in the leaves which will display dead spots, crinkling, spotting, or small brown spots. Another sign of a cannabis calcium deficiency is new leaves will appear small and distorted with curled tips The insides of the plant and well as the flowers/buds may show signs of decay. Roots may show signs of bacteria and may be dying off or be under developed.



Problem: Leaves may become yellow in between the veins, with mottled brown spots on the affected leaves. These brown dead patches may spread and eventually kill the leaf. Leaves may also shred and fall apart.

Overall growth of the marijuana plant may be stunted.

Masterblastman said:

My leaves develop brown spots late in veg and it gets worse through flowering and the eventually get crunchy and brittle. Anyone know what's going on? I'm using ro water and Humbolt county's own nutes and fox farm soil. View attachment 3347442View attachment 3347443 View attachment 3347444

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Ro water use tap water that looks like a bad case of cal mag defiency
Using tap water has many benifets they contain many trace minerals

But to fix ur prob buy some cal mag and feed also do a foliage feed of epsons salts u can buy from any supermarket
Simple get a 1 litre spray bottle and mix in about 2 teaspoons of epsons and spray plants about a hour before lights on

People and fucken cal/ mag.

I add 5ml a gallon of calimagic to start then add all my nutes to that mix

What kind of light are you using?

Gavita 1000s