Worldwide, natural environments are increasingly disturbed by climate change, land-use change and pollution. There is an urgent need for a better understanding of the overall functioning of earth’s marine ecosystems. Interactions at the basis of marine food webs are yet to be fully understood. Determination of the role of bacteria in the microbial food web and their interactions with first-level consumers, i.e. harpacticoid copepods, are pivotal for benthic ecosystems and aquaculture applications. Aquaculture experiences growing pressures to increase sustainable practices. Therefore, the effects of bacterial biofilms on copepod feeding ecology and energetic value, in particular polyunsaturated fatty acids, needs to be investigated. Especially fecal pellets are of interest to understand copepod coprophagic behavior and to quantify the importance of bacteria-assisted degradation of food sources, so-called microbial gardening. This proposal aims at the possibility of steering the energy flow at the basis of marine food webs by the development of artificial and modified carriers with selected biofilms. The new insights can support the development of sustainable feeding alternatives to Artemia including associated biofilms for aquaculture applications.