Evaluating the effects of organic carbon on biological filtration performance in a large scale recirculating aquaculture system

▶ Recirculating aquaculture conditions inhibit nitrification compared to lab studies. ▶ Increased organic carbon reduces biofilter nitrification performance. ▶ Increased organic carbon under normal conditions further reduced nitrification by 50%. ▶ Improving mechanical filtration and feed quality will minimize biofilter impacts. ▶ Future studies should be more indicative of biologically available organic carbon.