Root rot? How to fix mid flower

Beneficial fungi or salt build up. I’ve had the same my last grow. The spots were gone when plant began to consume more water. If it’s salt build up you may just water the plant thoroughly and use moist tissue to remove the spots if you don’t like them :)

Look up enter neem seed meal does. I think you have powdery mildew….

oh, is that stuff on side not "salt" buidllup? (solutes.. better term casue ppl associate weird stuff to "salts" in this contexxt) meh.. a portion of what i wrote below is irrelevant if so. We can't discern good fungus with bad fungus with our eyes. you could spray something on pot but it won't fix the problem growing inside if it's a fungus that competes vs a mutually beneficial microbe. give a 1-2% h2o2 drench if you think it is the cause. that will reduce beneficial microbes too. i still think you have some nute imbalance too.. mutlple causes are present here i think.

the buildup on pot is not the cause. i've used fabric pots with far more scaling than that with no problems. Gnat larvea damage roots, so this could be related to the spots you see. The progression of the paling is weird.. looks more dominant at top. knwoing ppms of what you fed lately would help greatly. i bet teh answer will stick out like a sore thumb. make sure pH is in decent range too. within a fraction of 6 is good. safer to err above 6 then below. various molecules quickly become more dfficult for the plant to use below 5.8. When difficult to diagnose it's more often ph or nute balance at issue... the gnat larva chewing on roots will have their say too. in future -- preemptively use BTi - in NA a product is called "mosquito dunks" and "mosquito bits". anythign with that same active ingredient will work same way (BTi). it's a mocrobe that causes larva to die in one way or another. It takes 2-3 weeks to quell an existing infestation, but if you use it preemptively shortly after sprout, you won't see any problem later. The soil and cooc et al we buy is often stored outside.. ti often comes with gnats. some brands are better thanothers, but all have the risk. it's not 100% effective, so you may see 1 or 2 gnats at a time, but never more. a sticky trap will collect those.. .you'll see it's very clean at end, but will snag a few. point is, it's cheap and you can easily avoid fungus gnats preemptively.

I would jump straight to root rot. To identify that you have to look at the roots. I get those spots all the time. It's probably just the mycelium. I look like you are starting to get a deficiency of some sort but to be sure I'd have to see the rest of the plant. One leaf usually isn't Eno to declare a problem.