DIW (pure deionized water) 780 ml
1M K2HPO4 (dibasic) 4 mL
1M KH2PO4 (monobasic) 16 mL
Difco Bacto Peptone (not Proteose Peptone) 3.2 g
Difco Bacto Agar 12.0 g
Mix by swirling (no need to dissolve). Autoclave 10 min. Cool to 45–50° in a water bath, and pour plates about ½ full.