I mix my supersoil in smaller amounts, multiple times, then combine it in a large trashcan to cook. I believe this lets me get a better mix, because I know that every ingredient will be mixed in every 5 gallons.
here is my recipe for 5 gallons of my own supersoil:
30 cups base soil (I use roots organics)
45 cups worm castings
6 cups roots organics marine green
6 cups ancient forest
2 cups Fox Farm "Marine Cuisine"
3 cups Mexican bat guano
3 cups Indonesian bat guano
2 cups Seabird guano
2 cups Rock phosphate
1 cup blood meal
1 cup bone meal
2 cups alfalfa meal
3 cups kelp meal
1/4 cup gypsum
10 cups light warrior
1.5 tbsp epsom salt
3 tbsp lime
6 tbsp mycorrhizae
4 tbsp azomite
I add each ingredient into a 5 gallon bucket, while mixing it well, when im done i dump it into a big 55 gallon trash can. Once it is full, I water it with a bit of molasses water, put the lid on, and let it cook for a month. During that time, dont touch it. Just let it sit, i put it somewhere that gets a few hours of sunlight, dont try to mix again or stir it, that will mess it up and not let the mycorrhizae do its thing. Once the supersoil is ready, after atleast a month, I add it to the bottom 1/4 to 1/3 of the plants pot, fill the rest with base soil, and use nothing but tap water and molasses throughout the whole grow. Just harvested and I had great yields, potency, taste and smell. My stuff came out as good as any dispensary stuff i've seen here.
Next grow I'm going to up the nitrogen ingredients a little bit. Prob replace half the base soil with more worm castings and another cup or 2 of the guanos/kelp. Other than that, I like my recipe.