Abstract: A drum filter assembly comprising a hollow drum filter having a longitudinal axis and an outer filter screen or mesh material, the drum filter being supported on external rollers for rotation about its longitudinal axis and an inlet for introducing liquid to be filtered into the interior of the drum filter. Rotation of the drum filter is effected by the liquid flowing into the drum filter. Alternatively, the drum filter may be driven by an external motor.

Abstract: A self-contained aquaculture system comprising a modular building defining a first main chamber for containing fish or marine invertebrates, a second swirl chamber comprising a primary filter communicating with the main chamber for removing solids from the main chamber, a drum filter for receiving and filtering water from the swirl chamber, a third biological filter chamber beneath the drum filter for receiving water therefrom and a biological filter tank. Water is pumped from the chamber. The building defines an enclosed space over the chambers, the temperature of which is controlled by an air conditioning unit. A foam fractionator, ultraviolet unit and ozone generator are used for treating the water in the main chamber.