First Grow Mephisto Sour Stomper Autoflower

With the dropping temperatures I’ve been struggling keeping my humidity above 50%, I’ve gotten a humidifier and put it outside the tent, hopefully that helps a bit. Noticed some yellowing on seed ones flowers, I think it’s in need of nutrients. I gave it two tablespoons of 2-8-4 Gaia green bloom, hopefully that will remedy it. I’ve never ph’d water up until this week. Water from the tap after sitting 24 hrs with a bit of calmag was ~7.5, dropped it down to 6.3-6.5 for the two waterings it got this week. I also gave seed 3 two tablespoons 2-8-4 Gaia green bloom as I haven’t given this plant anything since sprout. I’ve noticed quite a few gnats flying around in the tent which I don’t like. I got a bunch of the yellow stickies that seem to be catching a bunch. I think I overwatered, but not sure what caused all these fuckers, I’ve pointed the fan more directly at the dirt. Buds on seed one are continuing to develop well, looking super frosty so far.