Microbial communities in various components of a RAS system raising Walleye (Sander vitreus) paired with an aquaponics system were surveyed using metagenomic sequencing over a one-year period. Components sampled included the mineralization tank, biofilter and plant trough. The system was seeded with a commercially available mixture of nitrifying bacteria and the nitrifying community assemblage was also followed over-time.
Results showed ammonia-oxidizing bacteria (AOB) played a major role in ammonia oxidation compared to ammonia-oxidizing archaea (AOA) while nitrite-oxidation was dominated by species of the Nitrospira rather than Nitrobacter nitrite-oxidizing bacteria (NOB).
Results showed that were significant differences in microbial abundance and diversity in and between the three components of the system. In addition, over time the community make-up also varied. The significance of these change will be of importance to culturists.