I used Vero E6 cells and Mayaro virus. The virus was diluted in DMEM without FBS. The plaque media was 2X MEM, prepared with sodium bicarbonate and L-glutamine, adjusted to a pH of 4 with sodium hydroxide before autoclaving, and readjusted to a pH of 7.34 with HCl after autoclaving. Incubation was 2 days and I got this after staining.

I'm not sure the virus dilution media affected the virus becuase this is the same media I previously used with the virus and plaques were distinct although I lost some cell monolayers which was the reason for doing it again.

Thank you for your assistance.