Phytobenthos form biofilm with other microbial populations, including heterotrophic bacteria, which can also produce extracellular polymeric substance to help establish biofilm. Within these diverse communities, phytobenthos sustains the heterotrophs and mixotrophs not only by serving as food themselves. Phytobenthos can fix organic matters as primary producers, and the extracellular polymeric substance they produced to attach themselves to surfaces can also be utilized by bacteria as another potential carbon source. The presence of consumers are not the only biotic factors driving changes to the phytobenthos composition in the community. Photosynthetic populations that demonstrate themselves to be competitive can also change the benthic community makeup. The diatom D. geminata can proliferate quickly and are readily adaptive to changes to the aquatic environment.
Researchers have assigned trophic values or indicators based on the Periphyton Index of Trophic status (PIT) to phytobenthos as another means to determine the ecological status of water bodies. Researchers have also taken into consideration of the water chemistry, richness of the community, and biomass in their studies. Depending on the site of study, researchers also account for the activities from the phytobenthos when calculating for primary productivity.