@PhunkyPhallus,
Sorry for the late reply.
My soil base is 1/2 Happy Frog, 1/2 Ocean forest, mixed with worm castings, rice hulls, and seaweed compost. I moved away from Promix when I started the Earthboxes because I wanted to maximize the microbiology. This is actually my first grow without the mulch cover, they work great though and you get nice mycelium growth if you put Bokashi and ground barley on top of your top dress nutes. Things tend to break down pretty quickly under the mulch cover since it's always dark and worms/fungi love that.
I have a 1 inch mulch layer from chop and drop stuff on my current grow. A bit late posting it actually=/
Everything I learned about Earthboxes came from the BuildaSoil 10*10 grow series.
I learned soil microbiology from several books and vids, mostly Dr Elaine Ingam
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