Tami,
Thanks. Thanks for commenting and Good Luck.
Its not my method, just one of may in use, and has been used by many members.
Chivas,
USG Sheetrock. Waste pieces from Home Improvement store. Its almost pure gypsum, once the paper backing is removed. I checked out the granular gypsum available and it was closer to pelletized limestone. I will be using 2 table spoons / 5 gallons of mix to start.
Haven't figured out the Ironite as yet, but I will be starting with 1/4 cup / 5 gallon of mix at the start of the season.