Surface adherent microbial consortia, biofilm growth, is a predominant growth mode for bacteria and other microorganisms in nature. While there is considerable literature related to the negative aspects of the biofilms including chronic infections and industrial biofouling, they can also be harnessed as biotechnological tools such as in waste water treatment and remediation of environmental pollutions.
 
We are interested in identifying fluid conditions favouring or discouraging bacteria attachment and formation of biofilms and evaluating the role of the surface waves and vibration in the biofilm formation.
 
Our results show that the formation of the biofilms is strongly affected by the surface wave. Deterministic flows in a thin layer of nutrient medium promote the growth of patterned biofilms while chaotic and turbulent fluid motion reduces it. The settlement of bacteria and the locations of biofilms differ from the sedimentation patterns of inactive bacteria and of the passive microparticles, suggesting that the environmental factors dominate over hydrodynamic advantages. Wave-driven flows control the delivery routes of nutrients, oxygen and of the bacteria communication agents thus allowing to shape the biofilm development and to control macroscopic biofilm patterns. The results offer efficient tools to encourage or discourage the attachment of bacteria and allow shaping the biofilms using low-frequency waves.