The plants, insects and other arthropods, worms, nematodes and microorganisms all greatly increase in a system that isn't being ripped apart several times per year. The inputs of fish waste, rice hulls and etc, in addition are of course a stimulus. A necessary one when starting with an impoverished system. Once a system is healthy and building, I don't believe it should be necessary to fertilize or make potions on a regular basis.
