Metagenomic analysis shows diverse, distinct bacterial communities in biofilters among different marine recirculating aquaculture systems

Bacterial community analysis of marine recirculating aquaculture system bioreactors for complete nitrogen removal established from a commercial inoculum

“…Proteobacteria and Bacteroidetes were most numerous in samples of the nitrifying and denitrifying biofilters, finding that agrees with those made by Ruan et al (2015) and Huang et al (2016) for marine RAS biofilters. Even though present in large amounts in the CI, the percentage of bacteria from the Nitrospirae phylum were significantly reduced in the RBC; the relatively low abundance of these bacteria in RAS biofilters has been reported previously (Ruan et al, 2015; Huang et al, 2016).…”

“…The relatively low prevalence of these nitrifying bacteria in the RBC is consistent with findings for marine biofilters (Ruan et al, 2015; Huang et al, 2016). Conditions in the RBC were also favorable for proliferation of members of the family Nitrosomonadaceae , which is plausible considering their ammonia-oxidizing activity and the fact that they are regularly found in freshwater and marine aquaculture filters (Hagopian and Riley, 1998; Schreier et al, 2010; Ruan et al, 2015; Huang et al, 2016 ). Nitrosomonads increased from a very small occurrence of the CI to 11.4% of the RBC population and are likely the major ammonia oxidizing clade based on the predicted metagenomic analyses.…”

“…Characterization of the microbial communities in biofilters in RAS is of interest not only because it increases our understanding of the system’s microbial ecology, but also because it may provide the basis for managing such communities (Kumar et al, 2013; Michaud et al, 2014; Rurangwa and Verdegem, 2015), enhancing their function and reliability (Huang et al, 2016). …”

Effects of Hydraulic Retention Time and Influent Nitrate-N Concentration on Nitrogen Removal and the Microbial Community of an Aerobic Denitrification Reactor Treating Recirculating Marine Aquaculture System Effluent

“…For DNA extraction and microbial community analysis, 50 g of Kaldness K1 polyethylene media with biofilm was collected from the aerobic denitrification reactor at the end of each experimental phase. Huang et al [39] evaluated several methods-such as vortex, shaker, and sonication-to collect the biofilm. Following those findings, the Kaldness K1 polyethylene media was sliced into small pieces, shaken in a shaker, and centrifuged [39].…”

“…Keuter et al [38] showed that the nitrite-oxidizing community in a biofilter consists of at least two representatives of genus Nitrospira. Huang et al [39] collected samples from nine biofilters at five commercial recirculating aquaculture facilities with three different biofilter types, and showed the high abundance and diversity of nitrifying bacteria across these systems. Rud et al [40] showed that microbial communities differed between culture water and bioreactor biofilms and between salinities in salmon production systems.…”