I have a 6 row Orthman 1tripr. First year using it. I would like to try to shoot some P&K thru the fertilizer tube on the back of the shank. It seems 10-34-0 is readily available close by but I am only finding 0-0-15 as a source for the K. What are some ideas for liquid K and what are some of the rates you guys are using for the liquids? I will be planting soybeans. Thanks