It's been a long and badly-signposted road into the world of biostimulants up until last week. The market exists in that gray medium where expectations and promises are high, untethered by a lack regulatory standards and fishy marketing. Combined with the sheer variety of products promising monster roots and unbelievable harvests it's quite easy to feel overwhelmed with the options.
There are many many different bacteria and mycorrhizae that can promote plant growth, and most research repeatedly shows that a rich diversity of microorganisms is optimal since there's more of a "net" if you where to look at the flow of energy as opposed to a single "linear" flow from the single metabolism offered by only one type of microorganism. Additionally, amino acids have been shown to be best in a combination of each, but glycine (thanks to the bare-bones simplicity of the molecule) has been observed to produce the best results when used as a nitrogen source.
Some trial and error has led me to a couple certain improvements to my nutrient solution. I now start my seeds with some Superthrive and mix my substrate with small amounts of Great White and Agro Silicate powder. I add about 50 ppm of Silicate and half the recommended amount of Great White into my fish tank as well some 25 ppm of glycine. In one week my arugula shoots have exploded and my potted plants perked up like they just had the plant equivalent to an strong coffee.