Beef extract 10.0 gPeptone 10.0 gAgar 20.0 gTap water 250.0 mlSea water* 750.0 ml
Dissolve beef extract and peptone by heating in tap water, adjust pH to 7.8 and boil for 10 min. Readjust pH to 7.3. Add agar and autoclave at 121°C for 20 min. Cool to 50°C and add warm (50°C) sterile sea water. Liquid medium without agar should be combined when cooled to room temperature.
*Natural sea water is stored in the dark for at least three weeks to age. If natural sea water is not available use artificial sea water.
Artificial sea water:NaCl 28.13 gKCl 0.77 gCaCl2 x 2 H2O 1.60 gMgCl2 x 6 H2O 4.80 gNaHCO3 0.11 gMgSO4 x 7 H2O 3.50 gDistilled water 1000.0 ml