Prepare gelatin agar (M54), but add 30 g NaCl per liter. Suspend ingredients and boil to dissolve gelatin and agar. Adjust to pH 7.2 ± 0.2. Autoclave 15 min at 121°C. Cool to 45-50°C. Pour plates. If necessary, to inhibit spreading by Vibrio spp. such as V. alginolyticus, use 25-30 g agar/liter.
Original Source: Bacteriological Analytical Manual, 8th Edition, Revision A, 1998.