Ornamental Fish Production and Management

4.2.5 Trickle filter

It is a modified version of external canister filter. A stack of several trays with perforated bottoms are placed above the aquarium and used in conjunction with an external canister filter. The aquarium water after initial filtration in the canister filter is sprayed into the top tray from where it trickles from one tray to the other and is finally returned to the aquarium. The trays are part-filled with filter media and thus reinforce filtration. The main advantage of the trays atmospheric oxygen. Optimization of oxygen uptake of water results in enhanced bacterial activity.