Dry rusty leaves

Noticed you had a humidity dome on last week lol, never put a humidity dome on a plant with green leaf ever, just don't. It doesn't do what you think it does. What I see is moisture/vascular related but I couldn't think why it would have caused the dmg. Organnoman had a point with night and drooping but then noticed you had a dome. That'll do it 2 weeks into flower. Also your ph is 6. If you in anyway use organic nitrogen then your entire nitrogen supply will be released based on your ph level. Nitrification efficiency is around 15-20% capacity at a pH of 6 as opposed to a pH of 7 Biobizz lightmix uses 100% organic nitrogen Phosphorus is most important nutrient for a seedling. Between 6 and 7 phosphorous binds to oxygen. But at 6 it's getting critically low and will bind with iron and aluminum instead. Problematic so early in life. I would throw in a bunch more calcium with next balanced feed. Very important to keep tabs in pH when using organics as nitrogen can get trapped either way as a + or - both skewing pH. Ratio ratio ratio. pH is more than just a number; it represents the balance between acidic and basic components in a solution. Right now your balance is off. You need to understand why and how to rectify.

Looks like a cal mag issue You are getting those rusty spots and yellowing because the plant is not taking up enough calcium or magnesium Check your pH is around 6 to 6.5 in soil and add a cal mag supplement Damaged leaves will not recover but new growth should come in healthy once it is fixed. I recommend the Bio Tabs lineup because it keeps the soil life healthy and the pH well balanced so problems like this happen less often

This is not signs of a calcium deficiency.......cal/mag is not the answer to everything. Is it only one leaf?? Could be mechanical damage from hitting the edge of the potter, especially at night when the leaves are lowered and the fan blows on it. Nutrient deficiencies will show across the entire plant, not just a single leaf or two. Flushing the plant is pointless, it will achieve nothing. Same with nematodes, what are they going to do?? If that leaf is really bothering you, just cut it off. I really don't think you have anything to be worried about........unless it starts spreading across the plant. Remember too..........no plant will ever have 100% perfect leaves, 100% of the time.

Se for somente uma folha que estiver assim.... não se preocupe. Arranque essa folha e continue seu cultivo em paz .

hi there, if you gaveher too much water; distance to the lamp or the light watt is too high.... the queens start to get worde and the leaves turned yellow ....hope it went back to good

Kill them and start over!

Hi mate! Looks like early calcium deficiency, which is pretty common in young plants. Add a bit of cal-mag and make sure your pH is in range (6.3–6.8 soil). Should stop spreading in new growth once corrected. Happy Growing 🤠

Give her a flush and Cut the nutrients in half: she'll BE fine 👌🏻

looks overfed and a PH issue to me. Don't think nematodes would solve anything unless you had gnats.