Wtf is happening

Yoloo bro i kinda think is not Rust Fungus.... i think is eating too vigorous but the Nutes probably too much. Either you add some Calmag to make more resistant or just drop back a bit on the given feed. it doesn't look so bad. but surely not fungus to be fair. Happy Growing man 💚

Hey man, those leaves definitely look like they’re struggling with a deficiency. If you're using filtered zero ppm water, that’s likely your culprit. Zero ppm water is basically "empty," and if you aren't adding back minerals like Calcium and Magnesium (CalMag), the plant starts pulling them from the leaves, which causes those rusty spots and yellow edges. Organic amendments sometimes can't keep up with the demand if the water is too pure. I'd suggest buffering your water a bit or adding a dedicated CalMag supplement. Even with the same SOPs, some plants are just hungrier for those secondary minerals than others. Give it a shot and see if the new growth stays clean! Happy Growing Growmie 🌱

Carence En potassium Nocone_purpule à raison

That looks like a potassium deficiency (edge burn + necrosis), likely worsened by using 0 ppm water without enough minerals, so I’d add a proper base nutrient or CalMag + K source

Calcium deficiency, as others have said. Get problems but never change anything..................growing should be an evolutionary learning experience!

underfeeding and Ca deficiency it'll starve until ur organic shit works 😅

Change nothing and nothing will change, but different plants will ask for different ratios,this does look like calcium def could be from pk overload blocking like 00110 said

The other thing to consider is whether or not you overdosed with P or K. People often think bombing the plant with both in flower has some magical effect and is often instructed by the marijuana-branded fertilizer companies despite contradicting existing knowledge of nutrient uptake etc... Just damaging the local water table with the wasted fertilizer in runoff or worse, building up in your medium. (Did i get which is worse backward? LOL)

WOW LOOK AT DAT!!! DAT COULD BE DA FUNGUS ISSUE!!!

Calcium (CaO) deficiency