The compost of course, is a complete cycle all on its own, as it is food source AND microbes...
Microbes on their own,,, only consume OM until it is gone or unavailable...
Typical OM in lawns, come from clippings, leaves, ephemeral pinecones are great, even twigs and other seed debris may be mulch mowed for additional OM... when the microbes from Holganix or any other source are added to SPEED decomp, you MAY eventually run out of natural lawn debris...
Good question...
Does adding CARBON in the form of,,, Humates, actually feed the Holganix micro-organisms???
I guess,,, No... I believe that if the Humates are in the soil the plant will use them in a way that does not provide N, when consumed by microbes... I could be wrong...