Make six stock solutions, each with one of the following salts dissolved in 400
milliliters of water:
10 g sodium nitrate (NaNO3)
1 g
calcium chloride (CaCl2 ? 2H2O)
3 g magnesium
sulfate (MgSO4 ? 7H2O)
3 g potassium phosphate
dibasic (K2HPO4)
7 g potassium phosphate monobasic
(KH2PO4)
1 g sodium chloride (NaCl)
Take
10 mL of each stock solution and add to 900 mL of distilled water. Next add one
drop of 1% ferric chloride solution, 40 mL of Pringsheim's soil-water extract
and autoclave. This will give you a total volume of one liter of medium