Lower fan leaves turning yellow with brown spots.

Anytime there is a green discolouration all over with no obvious starting location its micronutrients. Doesn't mean it's nutrient related tho, first off without any history of feeding or watering we need a pH of your medium, feeding anything before finding thay out is counter productive. Npk are all mobile nutrients and would present distinctively on lower growth first. Calcium is immobile meaning ot would present as new growth. Brown spots could easily be from overwatered medium (oxidative stress) or any number of reasons. When pH goes high micronutrients become less available, Ph goes low nitrogen can be effected. Get a pH first, get a confirmation, if it's in range then apply your nutes again bit add a little bit grow fert too for first couple week of flower. I'd mention sulhpur but who uses that macronutrient pffffff. Bruh science nutrient.

Oh yeah don’t dial back the light at all you need all the light you can get to make the buds start to fatten up. Also after you flush the soil make sure to let the plant go thru a dry phase and let the soil get pretty dry it will help. No need to keep doing super dry phases over and over but doing it one time will help it recover

Hey there don’t worry to much I know exactly what is wrong and exactly how to fix it. You have a build up of nutrients in the soil the soil ph is way to low causing lockout I’m sure the soil ph is down below 5 if you don’t believe me run some water thru the pot collect some of the water and test the ph When you realize the ph is way to low all you need to do is take the plant to the bath tub and run about 5 to 10 gallons of regular tap water thru the soil most tap water has a ph between 7 and 8.5 that will bring the ph back up to a decent zone The spots on the plant will not disappear but the will not continue to eat up the plant. After you flush the soil make sure to give the plants a couple cups of water with flower stage nutrients make sure to ph that water to 6.5 or close The plant should start to get more green in less than 4 days The plant should start to get

Hey growmie, from the look of those leaves, I’d say it’s early nitrogen deficiency, maybe with a bit of cal-mag thrown in. Yellowing from the bottom up with rusty spots is a classic sign. Hard to be 100% sure without a diary, but if you’re only running Micro + Bloom, she might be missing some nitrogen — especially if the Grow part of the trio isn’t in the mix or was dropped too early. Also, might be worth checking your runoff pH. If it’s dipping below 6, even good nutrients won’t get absorbed properly. Aim for 6.3–6.8 in soil. Those darker specks could be a magnesium issue too, especially under strong LED lights or soft tap water. A bit of cal-mag might help smooth that out. Canopy looks a bit light-stressed too — if the light’s intense or too close, backing it off a bit might give her room to recover. She’s still got fight in her , tweak the feed, check pH, ease the light if needed. If you start a diary, tag me and I’ll take another look.