Fungus Among Us...

[Creeperpark]

Week 4. You have a good positive outlook and I know it will just be a matter of time before you get dialed in, and on your way to growing some super weed. Every setback is an opportunity to learn how to improve and move up in experience. The most important horticulture skill to focus on should be water management. Every soil has its own water-holding capacity and learning how much and when is what makes the difference between success and failure.

 

[StickyBandit]

IF you do have a fungus, anything with Bacillus Amyloliquefaciens in it is becoming more popular these days as it's completely harmless to plants and can be applied to ripe fruit and flowers right up to harvest
I would listen to what @Creeperpark is saying about watering. Pick up the pot to get an idea of the water it's holding.
Every time you pull a plant examine the root structure and check for water-logged areas or dry areas to see how your watering regime has been affecting root growth. What he says about different mediums is something you will learn with experience, as I'm trying to currently

 

[Three Berries]

If you have to spray potassium bicarbonate on your plants for mildew you are already screwed.

I would assume it would be a good preventive measure too. Better than any synthetic or copper based stuff IMHO. Mix it with a little glycerin and it will stay active from the humidty in the air.