Rapid start-up of a biological filter in a closed aquaculture system

Seeding of new biological filters with nitrifying bacteria is effective in reducing activation time of the new filters. In a series of tests, seeded filters were activated in an average of 10.7 days, compared with 22.2 days for the unseeded controls. The shorter activation period results from the reduced time required for the nitrifying organisms to increase in numbers to their environmental equilibrium in the system tested.