F-5 Hardening Fixer

Water at 125F (52C) - 2500ml
Sodium Thiosulfate - 960g
Sodium Sulfite - 60g
Acetic Acid, 28% - 190ml
Boric Acid - 30g
Potassium Alum - 60g
Cold water to make 4000ml

This is according to Natural Color Processes by Carlton Dunn