Abstract: A circulating filter and aerator system is to be installed in a pond of an aquaculture system and includes a pump unit which draws water from the pond and which is adapted to float and extend into the pond at a desired depth, a filter unit with an inlet port and an outlet port, a first control valve which connects the pump unit and the inlet port of the filter unit and which controls water flow from the pump unit to the filter unit, a floating aerator unit which receives filtered water from the filter unit and which generates sprays of the filtered water to release harmful gas and to reintroduce oxygen into the pond, serially connected second and third control valves which connect the outlet port of the filter unit and the floating aerator unit and which control water flow from the filter unit to the floating aerator unit, a fourth control valve which is provided on the filter unit to permit release of air in the filter unit when water fills the filter unit, a fifth control valve which is provided between the