<p>Phytoplankton and phytoplankton ecologists are subject to extremely different temporal and spatial scales. For example, they show very different generation times and occupy spaces of very different relative sizes compared to the planet they both inhabit. Nevertheless, phytoplankton ecologists often attempt to apply their own time scales to the object of their study. This could be a problem for the results (and their interpretations) reported in ecological studies on phytoplankton that do not take into account the temporal and spatial scales on which the life of these microorganisms is based. Any attempt to explain how environmental variables may influence phytoplankton dynamics should therefore be based on adequate sampling frequencies and with an appropriate spatial resolution. These topics were analysed in detail back in the second half of the last century, but seem to have been neglected over the years. In this short opinion paper, we will attempt to highlight, in a serious yet light-hearted manner, some aspects of temporal and spatial scales that may be relevant in the study of phytoplankton and that should be considered by phytoplankton ecologists when presenting the results of their studies on these extraordinary organisms.</p>