Campden tablets are easy-to-use capsules of potassium metabisulfite to help prevent oxidation and growth of wild yeast and bacteria.
1 tablet per gallon equals 30 ppm free SO2. 1 tablet will remove chlorine and chloramines from 20 gallons of water.
Each tablet is about 0.5 g.
2 oz is approximately 100 tablets; 16 ounces is approximately 800 tablets