Biology · Environmental Biotechnology & Ecology

With reference to biofilters used in Recirculating Aquaculture Systems (RAS), consider the following statements: I. Biofilters primarily host nitrifying microorganisms that convert ammonia first into nitrite and then into nitrate. II. Such biofilters generally require an initial conditioning period before they can efficiently stabilize nitrogenous waste loads. III. The efficiency of biofilters improves under strictly anaerobic conditions because nitrification does not require dissolved oxygen. Which of the statements given above are correct?