What color is coccus under a microscope?

Answer 1

All bacteria, including cocci, are colorless under the microscope unless you use a light filter or a stain. If you use a light filter or a stain then the color depends on which wavelength the filter is for or which type of stain you are using.

Answer 2

Coccus bacteria can appear in various colors under a microscope depending on the staining method used. Gram-positive cocci, like Staphylococcus aureus, typically appear purple, while Gram-negative cocci, like Neisseria gonorrhoeae, may appear pink after staining. Additional dyes or techniques can also be used to make them visible.