iNaturalist is primarily for wild organisms, but it doesn't matter if they're macroscopic or not. There are some iNaturalist projects specializing in microbes

iNaturalist is primarily for wild organisms, but it doesn't matter if they're macroscopic or not. There are some iNaturalist projects specializing in microbes (more than just these two). A project isn't necessary to submit observations, but it can help bring it to the attention of others able to verify your identification. https://www.inaturalist.org/projects/microscopic-microbes https://www.inaturalist.org/projects/microscopic-microbes https://www.inaturalist.org/projects/cyanoscope https://www.inaturalist.org/projects/cyanoscope