Small doses, big troubles: Modeling growth dynamics of organisms affecting microalgal production cultures in closed photobioreactors

► Model realistically simulates growth of contaminants in a production photobioreactor (PBR). ► “Sudden” onset of contamination can be attributed to exponential growth. ► PBR management protocols can reduce the risks of serious contamination. ► Small numbers of sufficiently fast-growing contaminants can lead to loss of algal cultures in days. ► A simple and cheap protocol for short-term prediction of severe contaminants in PBRs is presented.