This calculator expands on the TOSNA process provided at Mead Made Right.
A Tailored Organic Staggered Nutrient Addition, or TOSNA, supersedes the standard cookie cutter nutrient regimen that most mead makers have learned to follow in their mead making ventures.
One size does not fit all. Underfeeding your mead will undoubtedly cause many of the issues experienced by most amateur mead makers, such as stuck fermentations, severe drop in pH, and an increase in sulfur and fusel alcohol production.
TOSNA uses only Fermaid O because of its organic form of nitrogen which the yeast is easily able to metabolize throughout the entire fermentation process, unlike the inorganic form of nitrogen provided by the use of DAP and Fermaid-K.