An extra benefit of using Pectic Enzyme is an increased yield. Yeast nutrient is basically urea, though highly purified. We have a good supply for you at the Brewing Station. Think of it as the yeast's vitamin pill. It is especially important in making mead.
Yeast nutrient is cheap and keeps well.
For sanitizing, use 18 tablets per pint of water. To purify a must before adding the yeast, use one tablet per gallon and wait 24 hours before adding the yeast. Heat destroys the sulfate, so the must needs to be cool . . before you add the Campden tablet. Potassium Metabisulfite Adds sulfate to your juice to fend off wild yeasts and mold, as does Campden Tablets. Use no more than tsp.