Biological Filter

Out with the Bad, In with the Good

How do we recirculate wastewater without making it toxic to fish? Ammonia, a compound found in fish waste, can be toxic to fish in high concentrations. To address this issue, we use a biological filter. This filter contains multi-surface beads, starter bacteria, and a container where the process takes place. The biological process is part of the nitrogen cycle, specifically a process called nitrification. During nitrification, ammonia from the fish wastewater is oxidized first to nitrites, and then to nitrates by nitrifying bacteria. After this process, the water is once again safe for the fish, and the nitrates are absorbed by the plants in the grow bed.