That's cool. If you can't source compost any other way. Buy a bag. A little does go a long way. I take a handful of EWC a handful of compost put in a panty hose. Then half a table spoon could be less of caps packs into the water depending on what stage I'm in (nute pack, root pack) and brew 5 gallon 24 hours sometimes 72 but rarely. Just that can double your yield and blow out your trichs.The caps packs look awesome but they seem really expensive. I'm sure a little goes a long ways but I can see going through the 4oz container quickly with new soil and a few compost teas. So far, going organic has seemed relatively inexpensive but this could be a bigger ongoing expense :-/
And I didn't see Black Gold at HD or Lowes, but Ace had the BG garden compost and I think seed starter mix too.