I emailed them and this is what they had to say.
Thanks for reaching out. The Coot's mix for 3.5 cubic ft would be the following mix:
For Mixing in Soil (per cubic foot):
1 cup Crustacean Meal
1 cup Kelp Meal
1/2 cup Neem Cake
1/2 cup Karanja Cake
1 cup Basalt
1 cup Gypsum
1 cup Calcium...