Oxygen microsensor-based measurements and microscopy were used to characterize spatial photosynthetic zones and biofilm structure, respectively. Nutrients were analyzed using ion chromatography and TOC/TN analyzer. Lipid composition and quantification were determined using gas chromatography flame ionization detection (GC-FID) and mass spectrophotometry (GC-MS). Drip flow reactors (modified to allow for phototrophic growth) were utilized to study algae-bacteria interactions under sterile conditions