|Biocides against aeroterrestrial algal biofilms on man-made surfaces should be replaced by environmental-friendly strategies, e.g. photocatalysis. To evaluate the potential of antialgal strategies, their efficiency has to be verified. This study investigated, how such analyses can be performed in consideration of (1) morphological and physiological adaptations of aeroterrestrial algae, (2) their living in biofilms and (3) characteristics of antialgal strategies. Secondly, this study examined and evaluated the efficiency of different antialgal strategies.