The great googly one says : Poor drainage will cause both the leaves to yellow and buds to drop off. Another cause of yellow leaves is soil with a high pH. Too high, and the gardenia isn't able to take in nutrients including magnesium and iron, resulting in yellow leaves. Buds dropping off can...
I haven't messed much with making teas, but in general, it is my thinking that usually if you're looking for microbes, time is the most important addition. I would let it run as-is for a few days at least before worrying.
Bear in mind you are talking about reducing the light hours for an auto, which kind of defeats the purpose of an auto. (being able to continue to use and process 18+ hours of light to produce its' flowers)
Ideally, the longer you can let the auto have full hours the better result you will get...
No you don't need it, if you are unconcerned about the smell. The filter is to reduce/remove smell and the pre-filter is just to prevent the filter from becoming prematurely clogged.
I feel like even if one of your neighbors gets a momentary whiff, they won't clearly be able to identify where...
I find that they *can* still germinate at lower temps, it just takes longer. (usually about 1 week in a 70ish degree room)
It's definitely risky tho, not a good plan if the seeds are older- they can get soggy and die before sprouting sometimes.
I can't cite specific incidences, but I've used various expired ferts numerous times. I would say in general, as long as they have been kept in reasonable storage (not wet or overly hot) they've always been fine. My houseplant food container is (sadly almost empty now) almost 30 years old, and...
The dark green leaves appearing are the plant trying to get more energy for the root, because she still wants to be pollenated. That's why she's throwing so many fresh pistils. Sometimes, you just have to give them a deadline and cut, no matter how much they want to live.